Flip through the book

The first screen we ever installed hung in a gym in 2016. It ran inside an enclosure we had designed ourselves and showed content from software we had written ourselves. Not out of pride, but out of necessity: what you could buy back then looked like technology straight from a catalogue and did less than we needed. Our standards for design and function were higher than what the market sold as standard. That has not changed since.

That first surface grew into a totem we refined year after year: sturdier, brighter, easier to maintain. At some point the Swiss golf courses came to us. They needed surfaces that work in the clubhouse and out on the tee alike – sun, rain, frost, lawnmowers, the lot. We mounted indoor and outdoor screens in places where people usually think more about the greens than about technology. Ten years later those units are still there and still running.

That is the real lesson of those years, and it opens this book: a digital signage installation is not a piece of furniture you put in place. It is a medium that needs someone with something to say, and technology equal to the location. Hanging it up has become the easy part. What decides success or failure lies before and after: what do you want to achieve, who walks past, who looks after the content, and does anyone notice when the screen goes black.

Since then we have planned, installed and looked after hundreds of surfaces. Shop windows in the old town, totems in front of car dealerships, menu boards above counters, wayfinding in town halls, meeting rooms, hotel rooms, production halls and an advertising network that today covers more than five thousand surfaces. In that time I have learned more from the installations that did not work than from the ones that ran well from day one.

I have also learned that the attitude behind it counts. We build installations we would run ourselves, and we work with people who stand behind them. How we treat each other, within the team and with our clients, matters to me as much as any data sheet – in the end it decides whether anyone is still looking three years on.

This book is an attempt to pass that knowledge on before you pay for it the hard way. It is not a product brochure. You will find no model names and no prices here, but rules of thumb, working figures, checklists and a good many reasons why things go wrong. If you take away a single chapter, let it be the first: before you think about inches, resolution and mounts, spend two seconds imagining someone walking past.

Read the book front to back or jump straight to the chapter that is burning right now. Both work. And if you are left with questions this book does not answer: call us. I am always happy to talk about screens.

One Tuesday morning I was standing in a bakery in Olten, not looking at the croissants but at the customers. Above the counter hung a screen, neatly mounted, sharp picture, a video of a sunflower field with the word «pleasure». In twenty minutes exactly one woman looked up, and only because her child was pointing at it. The unit was working perfectly. It still did nothing.

The currency is attention

An installation is bought like a piece of furniture: diagonal, resolution, bracket, installation date. But it pays for itself in a currency that appears on no delivery note. Attention is the real currency, and it is scarce, because every person can spend it only once.

Whoever walks past your shop window has a destination in mind, someone beside them, a phone in hand and perhaps rain down their neck. Your screen is one of twenty stimuli within five metres. It does not win because it is bright and large, but because in the fraction it is given it delivers something useful.

Two to three seconds – that is the span we work with as long as people are moving. The figure does not come from a textbook but from standing beside screens and counting. It is uncomfortable, because it rules out almost everything that looks good in a presentation: the corporate film, the running text, three messages on one surface. And it is liberating as soon as you accept it. Whoever has only two seconds must decide – and that decision is the hardest work in any installation.

How people walk past screens

Eyes do not wander at random. Anyone walking looks slightly down and ahead, to where the floor lies four to six metres away. The head only lifts when something invites it: movement at the edge of the field of vision, a face, a jump in contrast. A display above that line has to fetch the gaze upwards first. That costs one of the two seconds.

This is why mounting height is not a matter of taste. Our rule of thumb: the centre of the surface sits at the eye level of the audience, roughly 1.55 to 1.65 metres above the floor when people are standing; in a waiting area, where they are seated, closer to 1.30 metres. Above doors and counters, screens often hang high only because that was where space was left.

The direction of travel matters too. A surface that only becomes visible once the person is level with it catches nothing but a profile.

• Is the surface in the approach path or only off to the side?
• Does the gaze have a clear run, or are display stands and promotional goods in the way?
• At what angle do people first see the surface?
• Is there a place where they have to stop anyway?

And then there is the phone. It takes exactly the seconds that would otherwise have been free: in a queue the head drops after ten or fifteen seconds of idleness, and after that you will hardly get it up again.

What gets through in two seconds

In two seconds nobody reads a sentence with a subordinate clause. What gets read is one large line, a number, an arrow, a logo. Our working limit is around seven words per image, and they should fit on one line, not three.

The second limit is type size. It depends not on the screen but on the reading distance: roughly 25 millimetres of letter height per three metres, measured on the glass and not in points in the layout program.

Then there is contrast. Dark type on a light ground wins in daylight, light type on a dark ground in the evening and against reflections. Thin weights and grey tones on photographs are the first to fail in sunlight.

Motion is both things at once: the best attention-getter and the most frequent disturbance. A change at the edge of the field of vision turns the head. Continuous motion, by contrast, has no beginning left for the eye to latch onto, and text that scrolls, rotates or flies in has finished building when the person has already gone. Move the transition, not the message.

Waiting place or passing place

There are two fundamentally different kinds of location, and almost every mistake in content planning comes from confusing them.

At a passing place people are moving: shop window, passage, station concourse, entrance area. Here the two-second arithmetic applies in full severity. One image, one statement, a change every six to eight seconds, so the next person still sees something whole. QR codes and telephone numbers are wasted here, because nobody stops to type them in.

At a waiting place seconds turn into minutes: waiting room, checkout area, lift, gym, hotel lobby. Whoever waits does not look once but again and again. Here content may go deeper, and here the QR code pays off, because a hand is free. But here you also need more variety: anyone waiting eight minutes sees a two-minute loop four times.

• Passing place: short, large, one thought, high contrast.
• Waiting place: more content, longer loop, changes by time of day.
• Mixed place, the checkout: keep it short on approach, fill it out in the queue.

In the gym you can see how strongly this works: anyone spending forty-five minutes on a cross trainer sees the same surface dozens of times – and notices every repetition.

The most common mistake

Almost every weak installation I have seen has the same cause: the screen shows what the client wants to say, and not what the person in front of it is looking for right now.

This happens in almost every project, because the content is created in a meeting room. Sitting there are people proud of the new machine, the anniversary, the mission statement. All of that is true and important. But standing in front of the screen is someone who wants to know where radiology is, what the lunch special is and how much longer it will take.

A simple test helps: write down the question of the person in front of the screen in their own words. «Do I have time for a coffee before my turn.» «Where do I have to go.» If your content does not answer that question, it answers nobody's question.

The second half of the same mistake is quantity. Show everything and you show nothing. Three messages on one surface cancel each other out, because the eye first has to decide where to begin – and it has no time for that. One surface, one thought.

And the third: eternity. A screen that has been running the same images since Easter turns into wallpaper – regular customers notice that faster than any analysis.

Count contacts, not reach

«Reach» is the word used to make numbers look big in advertising. For an installation on site it is of little use: a screen has no reach, it has contacts, and every contact has a duration.

Footfall times contact duration gives you the seconds that are genuinely yours. Repeat visits decide how quickly you have to change the content.

• Footfall: how many people pass the surface per day, spread across which hours?
• Contact duration: two seconds while walking, thirty in the queue, minutes in the waiting room.
• Repeat visits: passing trade rarely sees the same thing twice, regulars see everything ten times.
• Chance of being seen: how many of them can see the surface without turning their head?

You do not need to know these four figures exactly; an honest estimate is enough. They answer what otherwise stays stuck in gut feeling: how large the surface has to be, how long the loop should run – and whether a screen is worth it at this place at all. Two surfaces in the right spot beat six in the wrong one.

What of this can be measured later, and what cannot without monitoring people, is in the chapter on effect.

A guide through this book

This book answers a single question in eighteen attempts: how does a screen earn the two seconds it gets? Where technology is necessary, I explain it so that you can judge a quotation.

The first part lays the groundwork:

• Chapters 1 and 2: attention, and what digital signage actually is.
• Chapter 3: the location – light, sight lines, placement, the site visit.
• Chapter 4: the technology – displays, brightness, players, LED, brackets.
• Chapter 5: software and operation – management, schedules, monitoring, maintenance.
• Chapter 6: why we eventually built our own system, and what you can take from that for your own choice.
• Chapter 7: the content – what you show and how you design it.
• Chapter 8: infrastructure and law – power, network, Swiss data protection, music and image rights.
• Chapter 9: measuring effect without inventing figures.
• Chapter 10: the digital advertising network – your own surface or a booked one.

The second part goes to where the screens stand. Each of these chapters stands on its own; read the one that fits you:

• Chapter 11: food service – menu boards, daily specials, allergens, till integration.
• Chapter 12: hotel, reception and waiting area – lobby, rooms, seminar rooms.
• Chapter 13: meeting rooms and pro AV – picture, sound and controls that work.
• Chapter 14: wayfinding and orientation – buildings, public offices, hospitals, accessibility.
• Chapter 15: industry and internal communication – key figures, shift plans, safety.

The third part leads back to implementation:

• Chapter 16: the course of a project from the first idea to handover.
• Chapter 17: the twelve most common mistakes, with symptom, cause and remedy.
• Chapter 18: a sober look ahead.

Read it front to back, that is how it is meant – or start with the chapter that is pressing right now. Each one stands on its own and points to where things continue. At the end you will find a glossary and checklists for the site visit.

A screen does not win attention through size, but by answering in two seconds the question of the person standing in front of it.

«We'll just hang up a television» – I hear that sentence in almost every first meeting, and it is understandable. From the outside, a digital signage installation looks like a television on the wall. The difference is behind the glass: in the design for continuous operation, in remote management, and in the fact that someone is responsible for what runs on Monday morning.

A definition that holds

Digital signage means: screen surfaces in publicly or semi-publicly accessible places, centrally controlled, filled differently by time and location, designed for continuous operation. Four characteristics, and each one draws a line.

The television in the shop window meets none of them. It is built for a few hours of evening programming, not for ten hours of sun straight on. It knows no portrait format, drops into standby after a power cut instead of back into the picture, and can only be operated if somebody stands in front of it with the remote.

The video wall in the concert hall is the other extreme. It is stage technology: LED modules, an image processor, live feeds, a technician at the desk, built for one evening. That is not digital signage either, even though the same modules may be installed.

Between the two lies our field: an installation that starts itself in the morning, shows the right thing during the day, switches off in the evening and lasts for years without anyone checking on it daily.

The six building blocks of every installation

Whether one surface hangs in a bakery or fifty in a retail chain: the building blocks are always the same. If one is missing, you will notice within three months at the latest.

• The surface: display, totem or LED wall. Determines size, brightness, format, service life.
• The playback device: a small box or a system on chip built into the display. It fetches the content and shows it.
• The software: the management interface in the browser, where you upload content, set schedules and see whether all devices are online.
• The content: images, videos, templates, data from other systems. The only building block your customers ever perceive.
• The network: power and a connection by cable, wifi or mobile. Without a connection there is no remote maintenance.
• The operation: who maintains the content and clears faults. The one most often forgotten.

Hardware and software are bought and done. Content and operation carry on, week after week, and decide whether the installation is still worth anything after two years.

The families that sell

The shop-window display works behind glass against daylight. Brightness and heat are decisive: below 2500 candela per square metre the surface loses out in sunshine, and a unit without heat management drops out in summer.

The screen on the sales floor has an easier time. Indoor lighting usually lies between 300 and 750 lux, so 350 to 500 candela per square metre is enough. What matters is placement: at the shelf, where the decision is made.

Totem and digital pavement sign are the mobile variants. They need no hole drilled in the façade and can be moved until the effect is right. What matters is stability, cable routing and, outdoors, ingress protection – at least IP54 against splashing water and dust.

The menu board in food service is a discipline of its own. It is read from three metres, by people in a queue who decide within thirty seconds. What matters is type size, a calm structure and the ability to change the offer day by day without opening a layout program.

The families that guide and inform

The wayfinding system answers a single question: where do I have to go? Clarity and currency are decisive – a directory still showing the department from two years ago makes your building look unreliable.

Reception and waiting area are waiting places. Here content may run longer, here greeting visitors by name works. What matters is enough variety for eight minutes of waiting, without becoming frantic.

Hotel TV is a special case, because host and guest use the same device. The guest wants to watch television and stream, the house wants to show breakfast times, spa and weather. What matters is a system that separates the two and resets the room at checkout.

In the meeting room what counts is that the person walking in at eight connects their laptop and has a picture within thirty seconds; in between, the surface shows the booking from the calendar. In the production hall the key figures belong on the wall – units produced, rejects, days without an accident. What matters is large figures and a data source that is not fed by hand.

Large surfaces, dialogue and third-party advertising

The LED wall is not a larger version of the display but a different construction: individual modules on a frame, any shape you like, up to the size of a building. Everything is determined by the pixel pitch, the distance between two light points in millimetres. Rule of thumb: minimum viewing distance in metres equals pixel pitch in millimetres. Indoors we are usually between 1.5 and 3 mm, outdoors between 4 and 10 mm, but there with 5000 candela per square metre and more.

Touch and kiosk reverse the direction: it is not the installation that speaks, it is the person who asks. Product search, checking in at reception, ordering terminal. What matters is a short first level, a return to the home screen after inactivity, and glass that can take a knock – on public devices we look at the IK impact rating.

Advertising network surfaces are the special case where the surface is not yours. The site provides the space, a network operator supplies technology and operation, advertisers book time slots. What matters is availability and proof that the booked playout actually ran.

Applications compared

This overview shows where the requirements diverge – and why a device that is fine in a meeting room will not survive one summer in a shop window.

Operating hours is the underrated column: 16/7 means sixteen hours on seven days and is the normal case for commercial displays, while 24/7 demands a different design of panel and cooling.

From light box to cloud

The idea is older than the screen. The light box in the cinema foyer and the slide carousel in the travel agency were digital signage without the digital: a surface in the field of view, content that changes.

Then came the cathode-ray television with a video recorder, later with a DVD on endless repeat. Anyone who wanted to change the content brought over a new cassette. In the 2000s the USB stick took over, and that image still shapes the idea of the advertising screen today: a television, a stick, someone driving round the branches.

The leap came with two developments. First the player: initially a PC under the display, then a small box, today mostly a system on chip inside the device itself – a computer behind the panel, with no extra box and no fan. Second, management in the browser: since content has been distributed over the network, it makes no difference whether a surface hangs in the same building or eighty kilometres away.

In parallel the hardware became more serious. Commercial displays tolerate continuous operation and portrait format, can be switched via RS-232 or CEC and report their condition. That is the difference between a device and an installation.

What has really changed

When I am asked what has changed in ten years, most people expect an answer about resolution: 4K, 8K, HDR. That is the least important part. From three metres you can barely see the difference between Full HD and 4K, and the two seconds from the first chapter do not get any longer because of it.

Two other things have changed. First, operation. A fault used to mean: phone call, drive out, swap the stick. Today we see in the management system that a device has not reported in since Tuesday, and usually the matter is settled remotely before anyone on site notices. Schedules, switching times and updates run without anybody driving anywhere.

Second, the content. A surface no longer has to consist of finished images. It can draw on your own sources – menu plan, calendar, stock levels, weather, key figures – and on templates into which your team drops text. That removes the reason most installations fall into neglect: that every change costs effort.

Technology is no longer the bottleneck. The bottleneck sits where it always sat – in the question of what should appear on the surface.

It is not the picture that separates digital signage from a television on the wall, but continuous operation, remote management and a person in charge.

In a bakery on the Swiss plateau a screen hung above the counter, just below the ceiling. Neatly mounted, good content – but nobody looked. People stood a metre and a half in front of it, eyes on the croissants, and would have had to tip their heads right back. Two months later the same unit hung two metres further left, at eye level beside the queue, and suddenly it existed. The technology had not changed, only the place.

Sight lines and walking routes

Before I talk about inches, brightness or playback devices, I walk the route your customer takes: from the door to the counter, from the counter to the till, and out. A screen does not belong where a wall happens to be free, but where people are looking anyway.

Three questions I answer on every site visit:

• Where do people come from? Through which door, at what pace?
• Where do they look on the way? At the floor, at the goods, at their phone?
• Where do they stand still? Queue, reception, lift, cloakroom, changing room.

The still points are the most valuable thing about a location, because people who wait, read. In the gyms on our advertising network, the strongest surfaces are not in the training room but where people queue or get changed. Also check the sight line from a distance: does the passer-by see the screen from the street, or only halfway into the shop?

Mounting height and viewing angle

Mounted too high is the most common mistake we come across, and it has two causes: down below the wall is taken, and up high it looks more impressive. But a screen above head height demands a movement nobody makes when attention lasts two seconds.

Our working figures from practice:

• Centre of the picture at the eye level of a standing viewer, roughly 1.55 to 1.65 metres above the floor.
• If the audience is seated – waiting room, lobby, restaurant – the centre drops to about 1.20 metres.
• Bottom edge in landscape rarely below 1.10 metres, or people and furniture will block the picture.
• Portrait totem in a passageway: bottom edge at about 0.80 metres.

If a unit has to go higher because of doors or escape routes, tilt it downwards; five to ten degrees is enough and also helps against ceiling reflections. Think about the horizontal viewing angle too: many cheap panels already look washed out and colour-shifted at thirty degrees. If your audience walks past rather than standing in front, that counts for more than any resolution.

Distance and picture size

The question «what size do I need?» is really the question «from what distance should this be read?» What matters is not the diagonal but the letter height on the finished image. As a rule of thumb I calculate: letter height in millimetres equals viewing distance in metres times eight.

The third column applies to a normal layout of headline, short line and image. If you want to show a menu with many items, you need more surface or fewer items per image. Squeezing everything onto a 43-inch screen always ends the same way: the type gets small and nobody reads it. How content stays readable in two seconds is covered in the chapter on design.

The light on site

Light is what gets underestimated most often, because it changes over the day. Anyone measuring on a Tuesday morning under an overcast sky does not see what happens on Friday at four, when the sun comes in low through the glass front.

What I watch for on site:

• Daylight: how many lux fall on the planned surface? From around 1000 lux an indoor unit has no chance.
• Backlight: if the window is behind the screen, the viewer sees a silhouette. No amount of candela helps, only a different spot.
• Path of the sun: morning, midday, evening. An east and a west façade need different devices.
• Reflections: look at the dark glass surface from the viewer's position. What is reflected – a light fitting, a window, a refrigerated display?
• Colour temperature: warm light around 2700 kelvin makes cool screens look blue, and tight spots wash a display out.

The most effective countermeasure costs almost nothing: move a light fitting or aim a spot differently. Which brightness class suits which location is covered in the chapter on technology.

Portrait or landscape

Format is usually decided by instinct: portrait supposedly looks more modern, landscape is the normal thing. Neither is an argument. What decides it is the content you want to show over the coming years.

Portrait works when people are walking past and the content stacks up: individual offers, people, products, dates, directions. It works where the wall is narrow – a pillar, a niche, beside the door – and takes vertically filmed video without bars.

Landscape works for moving images, menu boards with several columns, occupancy plans and everything that sits side by side for comparison. In meeting rooms and hotel lobbies it is almost always right, because a laptop gets plugged in there now and then.

Two things matter more than the decision itself. First: stick with it – an installation of three portrait and two landscape screens doubles the design work for ever. Second: a consumer television must not simply be turned on its side. Continuous operation in portrait needs an approved device, otherwise heat builds up inside the housing.

The shop window: the hardest place

The shop window is the most tempting spot and the most demanding. Behind glass the unit sits in a small greenhouse: the sun heats the pane, the air behind it stands still, and an ordinary display eventually switches into thermal protection – usually on the afternoon when the most people are walking past.

What a shop-window position needs:

• High brightness, otherwise ambient light wins. Indoor brightness is never enough here.
• An operating temperature that suits the place, and a panel designed not to fade.
• Ventilation: a few centimetres of clearance from the pane, open at the top and bottom. A closed wooden box is an oven.
• Solar film or shading if the pane faces south or west.
• A night-time dimming. It spares the panel, saves power and does not light up half the lane.

Think about the back: from inside, customers would otherwise see a black surface with cables. And clarify early whether the landlord or the municipality has a say on illuminated signage – in old town locations that is the rule.

Outdoors: weather, vandalism, power

Outdoors, different laws apply. An outdoor unit is not an indoor unit with a roof but a construction of its own – which is why it is worth asking whether a shop window from the inside serves the same purpose.

What counts:

• IP rating: sealed against dust and water, typically IP65 all round. The rating has to apply to the whole housing, not just the front.
• IK impact rating: in publicly accessible locations it counts for more than any other line on the data sheet, and safety glass in front of the panel is mandatory there.
• Theft: fixings that need a tool, a lock on the service hatch, no visible cables.
• Foundation and statics: a free-standing totem needs a foundation that can take wind loads. Façade insulation is not a base.
• Lightning and surge protection: free-standing installations belong in the building's lightning protection concept.
• Power supply: anyone who plans the cable run only after ordering digs twice.

Cold is as much an issue as heat: good outdoor units warm themselves up before starting, so the panel does not become sluggish below freezing.

The site visit

A site visit rarely takes more than an hour and saves half days later. We come with a lux meter, tape measure, ladder and camera – and if possible at a busy time of day, not on a quiet Monday morning.

What we record:

• Lux measurement at the planned surface, at least twice in the day, plus the colour temperature of the lighting.
• Distances: shortest and typical viewing distance, free wall width, ceiling and door height.
• Photographs: head-on, from the viewer's angle, from a distance and once of the back of the wall.
• Power socket: where is the nearest one, on which circuit, is it switched off at night?
• Network connection: is a cable to the surface possible? If only wifi, measure signal strength at the mounting point, not at reception.
• Wall construction: brick, concrete, plasterboard, insulation, glass. Where are the load-bearing elements, where do the services run?
• Escape routes and fire protection: cover nothing – no emergency light, no fire extinguisher, no signage.
• Heritage protection: in protected locations a permit is required, even for a device behind the window.
• Lease: who is allowed to drill, and what has to be restored when moving out?

This list answers three things: device, bracket, connection. Fill it in before ordering and you will drill exactly once.

A screen belongs where people stop – and at the height they are already looking.

A furniture store called us in July: the large screen in the entrance was black, for the third time in two weeks. Nothing was broken – the unit was a television from an electronics market, built for three hours of evening programming, and since March it had been running twelve hours a day in portrait next to a glass façade. It had shut itself down to save itself. Technology rarely decides whether something looks good, but whether it still runs in three years.

Professional display or television

The question comes up in almost every conversation, and it is a fair one: a television costs less and has the same diagonal. The difference is not in the picture but in everything that comes afterwards.

Then there are details that only hurt in everyday use: a channel logo burning itself into the panel as image retention, advertising on the home screen, no remote shutdown for a hundred devices. For a meeting room used twice a week, a television is fine. For anything showing the same picture for hours every day, it is the more expensive route.

Brightness in candela

Brightness is given in candela per square metre, often called nits. It is the one figure on the data sheet where a wrong choice is immediately visible – to everyone, every day.

Aim too low and you do not get a slightly weaker picture but no picture at all: the display looks grey, colours tip over, text disappears into the reflection. Turning it up does not help, the maximum is already reached.

Conversely, too bright is no goal either: a shop-window unit at full power in a waiting room dazzles and ages faster. The right choice is a device that manages the peak and can be dimmed by sensor or schedule. Check whether the figure applies to the panel or to the finished front: safety glass and film swallow brightness.

Panel, resolution and format

Four K sounds like the better choice but rarely decides anything: whether you see more resolution depends solely on the viewing distance. On a 55-inch screen from four metres the eye no longer resolves the difference from Full HD. Four K becomes worthwhile where people come close: touch totems, menu boards above the counter, diagonals from around 86 inches.

More important than the pixel count are three other properties:

• Viewing angle: an IPS panel keeps its colours from the side, cheap VA panels go flat. Anyone walking past almost always sees it at an angle.
• Anti-glare: a matte surface rescues more locations than extra brightness.
• Still images: professional panels have countermeasures against image retention, such as pixel shift.

For format, what the chapter on location says applies: the content decides – but be consistent. An installation of identically oriented devices saves every second hour of design work.

Playback device: SoC or external player

Every professional display today has a computer built in, the system on chip, SoC for short. The signage software runs directly on it – for most installations the right choice: one device, one cable, no second source of error, no signal loss, no fan.

An external player becomes necessary if one of these applies:

• Processing load: elaborate animations, several videos running at once, very large surfaces.
• Special software: an industry application or an integration that exists only for Windows.
• Touch: kiosk applications with forms or search respond noticeably more smoothly.
• Several zones on one picture, for example occupancy, weather and video at the same time.
• LED walls, which need their own signal processing anyway.

Check before buying how long the manufacturer will supply the SoC with updates. A display lasts ten years; a platform often demands a newer runtime environment after five – and then a small player is the cheaper extension.

The LED wall

An LED wall is not a large display but a component made of many modules. Its most important measure is the pixel pitch: the distance between two image points in millimetres. Rule of thumb: the minimum viewing distance in metres corresponds roughly to the pixel pitch in millimetres.

Indoor and outdoor modules differ in brightness and encapsulation; an indoor module outdoors will not survive a winter. Before ordering you also have to decide:

• Maintenance access from the front or the rear. Without either, every module change becomes a building site.
• Spare modules: two to three per cent of the surface in stock, from the same production run; buying later means colour deviation.
• Power draw: a wall pulls several times its average at peak, and the supply is dimensioned for that.
• Frame construction: the substructure must be level, otherwise module edges show up in the picture.

Touch, kiosk and operation

As soon as people are meant to touch a device, the requirements change: a touch display is not a display with an extra function, it is a piece of furniture.

Capacitive surfaces respond like a smartphone: precise, glass, easy to clean – but they need a bare finger and fail with gloves. Infrared touch works with a light grid in front of the panel, works with gloves and a stylus and is cheaper at large diagonals, but becomes less accurate at the edges.

Just as important is the operation itself:

• Operating height: the active area belongs between roughly 0.90 and 1.20 metres above the floor; any higher and it is out of reach for seated people.
• Accessibility: approach space for wheelchairs, large buttons, sufficient contrast. In public buildings this is not optional.
• Hygiene: in practices and restaurants a surface that tolerates disinfectant counts.
• Return to the idle state after a minute, otherwise the next person sees what the previous one typed.

And reckon with people who press rather than tap: the mount must not wobble.

Bracket, enclosure and the underrated accessories

The mount is where people most often save money, and it causes the most trouble. What counts is the VESA standard, meaning the hole pattern on the back, and the permitted load – checked against the device weight, not against the diagonal.

• Wall construction: concrete and brick carry directly, plasterboard only via studwork, insulation not at all.
• Service access: a tilt-out mount saves a second person at every intervention.
• Cable routing: power and network into the wall or into a trunking; a bundle of cables devalues any good design.
• Theft protection: security screws, a locked mounting plate, and on totems a lockable service hatch.

The accessories forgotten in quotations that wreck deadlines:

• Cable lengths: HDMI becomes unreliable beyond about ten metres; above that you need active cables, fibre HDMI or network cable.
• The socket behind the device. It is missing more often than expected, and an extension lead across the wall is not a solution.
• Switching times via the display's own schedule rather than via a mechanical timer.
• A UPS where power cuts are frequent.
• Network: cable beats wireless. Wifi is the most common reason for screens standing still.

What really saves money on hardware

In digital signage the saving is not made at purchase but over the running time. The installations that cause us the least work almost always share the same characteristics.

• Standardisation: one product line, one type of mount, one playback path. Anyone with nine device types across twelve sites needs nine sets of instructions.
• The same models across sites: a change is tested once instead of nine times.
• A spare unit in stock: a display in the cellar brings a failed site back within hours instead of weeks. The same applies to LED modules.
• Remote maintenance: devices that can be switched, restarted and monitored over the network save most of the call-outs.
• Think in service life, not purchase price: a device built for continuous operation lasts twice as long as one used against its purpose. The second purchase is the most expensive.
• Night-time dimming: an installation that is dark at night uses less power and ages more slowly.

The most honest question before buying is therefore not what a device costs, but how often somebody will have to drive out – more on that in the chapter on software and maintenance.

The most expensive installation is the one someone has to drive out to: choose technology by how it will be run, not by the data sheet.

In a furniture store on the plateau the Easter promotion was still running in July. The screen worked flawlessly, bright, sharp, not a dead pixel – it was just showing rabbits. The sales assistant told me the marketing manager usually took care of it, and she had been on maternity leave since May. So the hardware was not the problem. Whether an installation is still right after a year is decided by the software and the people using it.

What software really has to do

Every signage package sells itself on its media library. That is the easy part. It gets interesting where everyday life begins: when three branches run the same menu board, one of them has its own lunch offer, and the apprentice is supposed to change the prices without wrecking the layout.

These are the points we check before recommending a system:

• Managing media: folders, keywords, an expiry date per file, replacement without a new playlist
• Playlists: order, dwell time per item, transitions, sub-lists for multiple lists
• Schedules by weekday and time, with a public holiday calendar and exceptions
• Zones and layouts: main area, side column, ticker, clock – freely placed, portrait and landscape
• Groups of screens: one change reaches every site in a region
• Roles and permissions: who uploads, who approves, who sees which sites
• A preview at the desk that matches the later picture
• Approval on the four-eyes principle
• Remote maintenance, status monitoring and a playout log

Many underestimate that log. As soon as you rent out surfaces or have to account for things internally, proof of play is the only paperwork that counts.

Cloud or your own server

Both routes work, and the choice has little to do with technology and a lot to do with your organisation. A bakery with eight branches wants to change prices from home. A hospital would rather keep its data in-house.

The last line is the most important. A decent player downloads its content and plays it from its own storage. If the internet fails, the screen carries on, only nothing new arrives. If a screen goes black or shows a loading symbol during an outage, its player is streaming instead of caching. For data protection the revised Swiss law applies: record where the data sits, who has access and what happens to recordings from cameras or sensors.

Scheduling is the real strength

A poster can do only one thing. Your screen can show something different at eleven than at four, and that is where the difference that pays lies. The bakery shows croissants and coffee until half past nine, then the lunch menu until two, cakes in the afternoon and from four the bread to take home. The same surface, four messages, no extra handling.

What should take care of itself through the schedule:

• Lunch menu, after-work offer, weekend and special opening days
• Public holidays, company holidays and Sunday operation in the shop window
• Promotions with a start and end date that switch themselves off
• A countdown to a date that gets smaller by itself every day
• Campaign periods that disappear after the last day

The most important point is the end date. Promotions nobody clears away are the most common reason an installation loses credibility. Give every item an expiry date as you upload it. An empty surface is better than a false statement.

Content that refills itself

The part of an installation that lives without an editor is the part that saves it. Any software worth the name pulls data from other sources and builds slides or zones from it. We set this up on almost every installation: it keeps the screen fresh even in a quiet week.

Proven sources:

• Weather and temperature, in food service happily with a pointer to the terrace
• Opening hours and an automatic note when closing time is near
• Queue system and ticket number in practices, public offices and workshops
• A calendar outside the meeting room showing the next booking
• Office spreadsheets for prices, duty rosters or availability
• Stock management and till system for stock levels, daily specials and promotions
• RSS for club and municipal news, web widgets for timetables or occupancy

A car dealership uses this to show the used cars actually available: if a car is sold, it disappears from the shop-window display the same evening. Only one thing matters: define what the screen shows when a source does not respond.

Who does what

An installation needs three responsibilities, and they have to carry names, not departments. The editor creates content and keeps to the plan. The approver checks the statement, the price and the spelling – and is a different person from the editor. The third role is the technical contact in case of a fault, often your IT department or us.

Put it in writing; half a page is enough: who maintains content weekly and how much time is set aside for it, who approves and within what deadline, who gets called when a screen is black, and who decides when the branch and head office have different ideas. That half page is the difference between an installation that runs and one where everybody assumes somebody else is doing it.

With several sites a mixture has proved itself: head office supplies the campaign and locks it against changes, the branch fills in two or three local slides itself. That keeps the appearance calm, and the site still recognises itself.

Maintenance and monitoring

A screen that is not running does not report itself – unless the software does it for it. Every player should check in at short intervals, and the system should raise the alarm when a check-in fails to arrive. A simple network reachability test is not enough: a device can answer and still have been showing a frozen image for days.

This is what basic monitoring covers:

• A status message per player with timestamp, software version and free storage
• A screenshot from a distance, so you can see what is actually running
• A scheduled nightly restart of player and display
• Switch-on and switch-off times via the display's schedule, not via the socket
• An overview of software versions, with updates outside opening hours
• A pre-configured replacement unit in the cupboard

The replacement unit is the cheapest insurance there is: a prepared second device turns an outage of days into an outage of hours. How displays are designed for continuous operation is covered in the chapter on hardware.

The three months afterwards

The decline of an installation follows a pattern I have been seeing in the same order for years. In the first month enthusiasm is high and new slides arrive every week. In the second month one person handles the upkeep on the side and the intervals grow longer. In the third month only the last promotion is still running and nobody looks any more. From then on the screen is a piece of furniture.

Only sobriety helps against this. An editorial plan over twelve months, with one line per month, is entirely sufficient – topic, person responsible, date. Plus a time budget written into someone's workload, even if it is half an hour a week. A good share of automatic content, so the surface does not age even in a quiet week. And a reminder in the calendar that always asks the same question: is everything running there still correct?

A gym worked out for me that upkeep costs a quarter of an hour on Monday morning – the realistic effort when templates exist. How such templates are built you will read in the next chapter.

Service contract and response times

At purchase everyone thinks about the device; in operation what counts is the contract. A service contract need not be thick, but it has to answer four questions: what is covered, how quickly is there a response, who comes, and what happens if a part fails.

Note the difference between response time and restoration time. The first only says when somebody gets in touch. What matters is by when the screen is running again and whether a replacement unit is standing by for that. For a shop-window display that carries revenue, that commitment is worth it; in a meeting room the next working day is fine.

It should also cover: remote access and how it works technically, responsibility for updates, spare parts over the years, the procedure in a warranty case, plus cleaning and on-site inspection on a fixed rhythm. Clarify as well who owns the content and how you get at your data if you change provider. That question comes up late and always at the wrong moment.

An installation does not die of its screen but of an empty calendar – schedule, data source and clear responsibility keep it alive.

We wrote our first playback system ourselves in 2016, alongside the enclosure for the first totem – there was simply nothing on the market that met our standards. Later, as the installations multiplied, we used off-the-shelf systems where they fitted. Until I stood beside the till in a bakery and watched the owner try to change the lunch menu: she clicked through four levels, found a timeline, moved an element by accident and ended up with a blank screen. The software could do everything – transitions, layers, video walls, permissions for a hundred sites. Everything except what this woman needed at six on a Tuesday morning. That was the day we started building our own again.

What bothered us about the off-the-shelf systems

I want to be fair: the systems of the time were not bad. They were built for somebody else – for chains with a marketing department, their own IT and people who use the tool every day. Our customers are bakeries, car dealerships, practices, municipalities; they spend twenty minutes a week with it.

Four things kept coming up:

• The licence ran per screen per month. Anyone operating many surfaces pays twice: for the hardware and for the right to switch it on.
• Most of the functions went untouched. Layers, scripting languages, animation curves – tools for designers, not for businesses.
• The interface assumed knowledge nobody had. After the training it went well for two weeks, then the branch manager called us again.
• Support sat in another time zone. A black screen on Saturday morning was dealt with on Monday afternoon.

On top came the question of where the content sits. For a menu board that does not matter; for meeting-room booking data it does.

What we wanted instead

We did not start with a list of functions but with five sentences on a sheet of paper. Each one was a decision against something else.

• A baker operates the system without training. If she needs a manual, it is the interface that is wrong, not the baker.
• Templates instead of design freedom: we set the grid, the typeface and the colour, the customer fills in text and image. Why that saves an installation is in the chapter on content.
• The data sits in Switzerland, on servers we can name. The revised data protection act requires knowing where data sits and who has access anyway.
• Every playout is logged. In our advertising network, that proof is the basis for billing; without it, third-party advertising cannot be sold seriously.
• The system knows our processes. A quotation becomes an order, which becomes a site with devices and a service history. If a player stops reporting in, the system knows who it belongs to.

The last point was the real reason. No off-the-shelf software knows your processes.

Start small and let it hurt

The first version could do exactly three things: upload images, put them in an order, send them to a screen. No schedule, no zones, no permissions. With that we went to three customers we knew well and said: try it, and tell us where it hurts.

It hurt in places we had not expected. Nobody missed transition effects. Everybody missed a preview showing what the slide would look like on the wall later. One branch manager uploaded the same image three times because after saving she could not see whether anything had happened. Things like that only show up where somebody works with it on a Tuesday morning under time pressure.

A rule came out of it: every new function needs a name and an occasion. Not «it would be nice» but «otherwise the municipality cannot show its referendum posters». We do not build functions without an occasion. That sounds strict and it saved us from a product that can do everything and helps nobody.

Five functions instead of fifty

After years in operation, actual use looks soberingly simple. The vast majority of installations need five things: upload content, put it in an order, control it over time, see the state of the screen, and reach somebody when it jams. Everything else is accessories.

Schedules beat effects. A bakery showing croissants in the morning and the menu at lunchtime gets more out of its surface than any animation. Automatic content – weather, opening hours, stock levels from the merchandise system – keeps the screen fresh even in a quiet week.

A screen that reports in on its own is worth more than any design feature. Our players check in at short intervals and send a screenshot on request. If a check-in fails to arrive, we find out before the customer notices. That has saved us many call-outs.

And less choice means fewer mistakes. Since the templates fix type size and line count, we hardly see illegible slides any more. Nobody has missed the freedom we took away.

What your own software really costs

I will not talk about the price here in figures but in obligations – those are more honest. Development is the smallest part and the only one that is finished at some point. Everything after it never stops.

What you take on if you build it yourself:

• Maintenance: player operating systems change, browsers change, interfaces to tills and calendars change. That is work no customer ordered.
• Security updates: a system reachable from the internet has to be maintained in the week a vulnerability becomes known, not next quarter.
• Availability: if our system stops, screens stop across German-speaking Switzerland. That responsibility cannot be passed on.
• Knowledge in more than one head: a system only one person understands is a risk.

For us it works out, because the effort spreads across many sites and across our own advertising network, and because the same system carries the processes from quotation to service call. For a business with four screens it never works out.

When an off-the-shelf system is the better choice

I do not recommend our system everywhere, and certainly not custom software to everybody. There are cases where an established product is clearly the better fit.

An international group with its own IT and sites in several countries needs a provider who fulfils contracts in different legal jurisdictions, presents certifications and brings a role model for hundreds of users. For that we are the wrong people.

Special cases with a fixed integration belong here too. If your branches depend on a particular till system and a proven signage extension exists for it, take that. Rebuilding an interface that already exists is expensive and thankless.

And very large networks sold programmatically need connections to trading platforms, standardised formats and counting methods that media agencies accept. Nobody builds that apparatus on the side; more on this in the chapter on the advertising network.

The rule of thumb is unspectacular: the more distinctive your processes, the more custom software pays off. The more standardised your requirement, the more likely it already exists off the shelf.

Questions to ask every supplier

Whether an off-the-shelf product or a provider with its own software: these questions cost ten minutes in a sales meeting and save a great deal later.

• Where is my data, on whose servers, in which country – and who at the provider can view it?
• How do I get my content back out? Is there an export, and in what format?
• How is the licence model built? Per screen, per site, per user – and what happens if I add or remove a screen?
• Is there a playout log, how long is it kept, and can I download it?
• How does remote maintenance work? Who can connect, is it logged, and can access be switched off?
• What happens if I change provider? Do the players belong to me, and can other software run on them?
• What happens if you no longer exist in five years?

The last question is uncomfortable, and that is exactly why I like asking it. Anyone who answers calmly and explains how, in the worst case, you get at your content and your devices, has thought about it.

Own system versus off-the-shelf system

I give the following assessment in conversation too – as a supplier who built his own, but without sugar-coating.

No single line decides it. Read the three that affect your everyday work.

Your own software pays off where your processes are genuinely your own – everywhere else you buy responsibility nobody ordered.

In a dental practice a large display hung above reception. On it ran a PDF page with the hygiene concept, eleven paragraphs, stretched into sixteen by nine as an image. Nobody read it, and nobody could have. The screen was well chosen, bright enough, neatly mounted. The only thing wrong was what was running on it.

The dramaturgy of a loop

A loop is not a folder full of files but a sequence with a rhythm. The useful length lies between one and three minutes. Anyone glancing while walking past sees one or two slides anyway; anyone waiting – at reception, at the till, in the lift – should not see the same statement four times.

Five to eight slides per loop is enough. More messages dilute the installation, because each one comes round less often. Do not order by importance but by alternation: calm slide, moving slide, calm slide. Two videos in a row feel frantic, two text slides in a row feel like a presentation. Better to place the most important statement at two points in the loop than to make it longer.

Places with waiting time follow a different rule from the shop window. In a waiting room a slide may stay longer and tell more, because your audience has time. In the shop window what counts is the stretch from the traffic light to the door, which is a few paces. The same loop never suits both – plan one per location.

One slide, one message

The most common cause of ineffective screens is not poor design but too much content on too little surface. A slide carries one statement. Show two and you show none.

Build every slide in three levels. An eye-catcher that says in half a second what this is about – an image, a number or a single word. A main line with the statement, five to seven words. Below that one line with the essentials: price, date, place. Nothing more is needed, and nobody reads more.

White space is not wasted room but the means that makes the main line big. A calm area around the statement works better from ten metres than a slide filled to the brim. Guide the eye: it begins top left or in the centre and ends bottom right – that is where the call to action belongs. And check every slide standing up at the real distance, not at your desk. The difference is sobering and instructive.

Typography at a distance

Type on screen is a different thing from type on paper. As a rule of thumb we reckon one millimetre of cap height per two hundred millimetres of viewing distance: at five metres the main line therefore needs a good twenty-five millimetres of height on the glass, not in the template. Measure it on the device; the figure surprises most people.

What counts at a distance:

• a medium to bold weight; thin weights disappear on bright displays, because the luminous surface eats the hairlines
• a typeface with open forms and a clear distinction between I, l and 1
• a little more letter spacing on small lines, a little less on very large ones
• lines of no more than five to six words; better to break than to shrink
• capitals only for short words; whole lines in capitals lose the word shape and read more slowly
• a strong brightness difference between type and background, checked in the worst light of the day

If a line does not fit, the sentence is too long – not the type too large.

Colour and contrast on screen

A display emits light; paper is lit. That is why colours look stronger on screen, and large bright areas quickly dazzle indoors. In a dark lobby a dark slide with light text is more pleasant. In the shop window in daylight the light surface with dark type almost always wins, because it holds up against the ambient brightness.

Your corporate design was made for paper and has to be translated for the screen. A delicate grey that looks refined on letterhead is barely distinguishable from white on a display. Keep the house colour and the accent colour, but allow yourself a stronger shade for type on a coloured ground. Two colours plus white and black are enough for almost any slide.

Think about red-green colour blindness: never carry information through colour alone, but also through word, shape or position. And look at your slides once at midday, with sun on the pane. What is readable then is readable. How bright a device has to be for which situation is covered in the chapter on hardware.

Motion, image and video

Movement attracts the eye – but only if it is the exception. If something is constantly moving across the whole surface, the eye tires and looks away. What works best is a calm slide that stays put and a change that fades in and out cleanly. Half a second to a second of crossfade is enough; anything playful – spinning, flying, bouncing – looks cheap by the third run-through at the latest. Flying logos are the surest way to make an installation look dated.

Videos on a sales floor run practically always without sound. That means the message has to be in the picture. Keep clips short, fifteen to thirty seconds, add subtitles or on-screen text and start with the strongest image rather than with a title sequence. Where music plays, settle the rights in advance; for public performance the relevant SUISA tariff applies.

With images, resolution comes first and the crop second. Use material at the resolution of the surface, in portrait accordingly vertical – a rotated landscape shot with bars gives itself away immediately. Stock images are allowed but look interchangeable: a shot of your own team, your shop, your workshop beats any purchased smile. And settle image and personality rights before a photograph goes onto a public surface.

Templates save the installation

Everything you know about design is worthless if the slide gets made on Friday afternoon by whoever happens to have time. Templates solve that problem. They fix placement, type sizes, colours and image crop, and the editor only fills in text and picture. An installation with templates still looks after a year the way it did on day one.

A useful family of templates has six members:

• Promotion: eye-catcher, offer, validity
• Information: opening hours, notices, procedures
• Menu or price list: multi-line, with a fixed column width
• Team or portrait: picture, name, role
• Event: date, title, place, registration
• Emergency or fault: one line, high contrast, usable immediately

The last is rarely needed and worth its weight in gold when the lift is out or the entrance is blocked. Create the templates in the same software that will be used later, not in a graphics program only the agency has. Who maintains and who approves is in the chapter on software and operation.

What never belongs on the screen

There is a short list of things that reliably devalue an installation. I see them everywhere, and they cost more credibility than any missing feature.

• Running text: nobody standing up reads more than three lines
• PDF pages and text documents as an image, margins and page number included
• Spreadsheet tables with gridlines and footnotes
• A news channel in the waiting area; a disaster report next to your offer takes the mood out of the room
• Expired promotions, outdated team photos, Christmas greetings in February
• A visible mouse pointer, a window within the window, an operating system message
• The wrong aspect ratio: squashed faces and black bars
• A clock or weather display frozen because the source no longer responds

Mouse pointer and system message are incidentally not a design error but a sign of a player running as an ordinary computer rather than in locked-down mode.

Working figures for everyday use

The following figures are not a standard but experience from installations that work. The height refers to the cap height of the main line, measured on the glass.

Two notes. The dwell time applies to still slides; a video runs for as long as it takes and should not exceed thirty seconds. And the word count includes everything there is to read, including the small print at the bottom right. If your count goes over the figure, cut – that is almost always the better slide.

Two seconds are enough for exactly one message – put two on a slide and you end up showing none.

I often stand in building sites, between dust and cable drums, and ask three questions: where does the power come from, where does the network come from, and who will be allowed to touch it later. At that moment the answers cost almost nothing. Six months later, once the plaster is dry, the same answers cost trunking, chasing work and three extra appointments. This chapter is about the half of a project nobody sees – and which decides whether the screen runs on Sunday morning.

Cable beats wireless

A network cable pulled while the electrician is laying conduit anyway is practically free. Retrofitted, the same cable means: taking off skirting boards, gluing trunking, opening ceilings. So run a network socket and a power socket to every place where a screen might one day hang. Two sockets too many cost less than one too few.

One cable later replaces three wireless devices. Up to around a hundred metres a Cat 6 run needs nothing in between, and with PoE the power comes with it: about 15 watts under IEEE 802.3af, about 30 watts under 802.3at. That carries a player, a sensor, an access point – not a 55-inch display.

A separate network for the screens

Screens do not belong on the same network as the till, and certainly not on the same one as guests. A separate VLAN costs your network administrator half an hour and spares you the question of whether the player in the shop window can see the accounts. I have taken over installations whose entrance totem was on the open visitor wifi, with the password displayed on a notice next to it.

Bandwidth is less often a problem than most people think, because a good player does not stream but pre-loads. The content is fetched overnight, sits on the device and plays from there. If the line fails during the day, the surface carries on – it just gets nothing new. It gets tight in distribution: twenty branches pulling the same video at once is noticeable. That is why updates belong at night, staggered across the sites.

At outdoor sites, mobile is often the more honest choice than a borrowed connection from the neighbouring building. And where an outage hurts, a mobile SIM as a second layer makes sense: it takes over when the fixed line drops out and sleeps otherwise.

Remote access, firewall, maintenance window

A signage installation needs surprisingly few connections. As a rule it is enough that the players may phone outwards: fetch content, report status, ask whether there is anything new. Nothing has to be open from the outside in. Port forwarding to a screen on the sales floor needs a very good reason. Maintenance runs over VPN or the management interface, not over a permanently open remote support service with a password from the year the shop opened.

Set the service provider's access down in writing – in the end it is half a page:

• Who gets access, to which devices, for what purpose.
• Individual accounts per person rather than one shared collective account.
• Two-factor sign-in for everyone allowed to publish content.
• How access ends when the collaboration ends.

Software ages in operation: players get new versions, operating systems get security updates, certificates expire. The last of those is the classic – suddenly a browser message is standing in the shop window, because an expiry date was in nobody's calendar. Put a maintenance window in a night-time hour, update a test device first, then the rest in waves. A scheduled restart once a week is not a weakness but hygiene.

Power that does not hang off a light switch

The most common power mistake is the most convenient one: the screen is on the same fuse as the shop-window lighting, and that goes off in the evening via a timer. Every evening the player is unplugged, every morning it restarts hard. After six months the memory card is damaged and nobody knows why. Give every surface its own permanently supplied feed.

The software should do the switching off, not the timer. Every usable control system knows a calendar, good displays accept commands via HDMI-CEC or RS-232 and shut their panel down themselves. The player stays awake and is there immediately in the morning. If you want to cut consumption, turn the brightness down at night; how to choose it in the first place is covered in the chapter on hardware.

Two things belong in the electrical planning and are gladly forgotten. First, wayfinding, displays on escape routes and emergency boards need an answer for a power cut – an uninterruptible supply or the rule that the printed board beside it takes over. Second, every fixed installation has to be connected and signed off by a qualified electrician. A cable running visibly to the socket may pass in an office; in a publicly accessible room it is a trip hazard.

Data protection in practice

Since the revision, the new data protection act, nDSG for short, applies in Switzerland. For screens that rarely means «forbidden» and almost always «say what you are doing». A surface that only displays collects nothing. It gets delicate as soon as a sensor is added.

Cameras and measuring sensors are permissible if they are proportionate and do not identify individuals. Cleanly built systems calculate inside the device: they count faces, roughly estimate dwell time or age group and discard the image immediately – what is stored is a number, never a face. Get that in writing and put a notice on the surface. A recording in which people are recognisable needs its own justification, a sign and a deletion deadline.

Two everyday cases I have to explain again and again. Anyone showing staff or customers in content needs their consent, preferably in writing – including for the team video somebody shot three years ago. And calling out names in waiting areas is a disclosure to everyone present; numbers or initials do the same job without half the waiting room learning who is sitting there for treatment.

Image rights, music and permits

Whatever runs on the screen belongs to somebody. Images from a stock library carry a licence, and that licence often distinguishes between editorial and advertising use, sometimes also between a screen inside the shop and a surface visible from the street. File the licence with every image; three years later nobody knows where the picture came from.

As soon as sound is added, SUISA comes into play. Music that is publicly audible is subject to royalties; for background music and audiovisual playback in businesses the joint tariffs apply, and which one applies depends on the surface, the use and the type of business. Settle that before the installation goes live. Many installations manage without sound anyway; why subtitles work better for passers-by is covered in the chapter on content.

Outdoors the municipality has a say. Screens and totems visible from public ground count as advertising and usually need a permit, regulated at municipal and cantonal level, with conditions on size, luminance and operating hours. Then there is glare: moving images in the field of view of drivers are judged strictly, often with minimum dwell times imposed. Ask the building authority early – a refusal after installation is the most expensive variant.

When something fails

Plan for the bad day while the good one lasts. Three questions are enough: what happens if the internet is gone? What if the power is gone? And what does the customer see during those minutes?

Without internet a properly built player carries on, because the content sits locally. Only surfaces that live on live data are critical – departure times, queue numbers, occupancy plans. For those you need a fallback: the last valid information with a timestamp, or a calm standard page with the logo and opening hours. But not an error message in white on blue, right in the shop window.

After a power cut every device has to start up by itself. That is a setting in the screen and one in the player, and it is set wrongly surprisingly often. Check it deliberately: pull the plug, wait two minutes, plug it in, watch the clock. Anything that is not playing by itself after three minutes will not play on Sunday morning either.

That leaves the service chain. Who notices the outage – you, your employee, or monitoring that reports as soon as a device goes silent? A pre-configured replacement unit in the store cuts every fault down to one drive and one action.

What you settle at construction stage – cable, power and responsibility – you never have to chase out of a wall later.

«Is this actually doing anything?» That question usually comes in the third month, and it is fair. But it cannot be answered as long as nobody has said what «something» is supposed to mean. A screen in a practice waiting room has a different goal from a surface in a bakery window. This chapter shows what is honestly measurable, what is only estimated – and how to draw decisions from it instead of having the same discussion every month.

First the goal, then the figure

Every measurement begins with a sentence you should write down before buying: what is this screen hanging there for? The answers differ – and they lead to different figures.

• Attention: passers-by should stop, the shop window should stand out.
• Selling a particular item: the lunch special, the subscription, the armchair in row three.
• Relieving reception: fewer questions about opening hours, forms, responsibilities.
• Shorter perceived waiting time: the same twelve minutes should feel like seven.
• Staff information: key figures, safety topics, duty rosters.
• Avoiding queries: wayfinding, prices, availability.

One goal per surface is enough: give a screen four jobs and you get four mediocre results. Also write down when you would be satisfied – not «more revenue» but «on days with screen advertising, more lunch specials go over the counter than on comparable days before». That sentence is the difference between an analysis and an opinion.

What can be measured – and what cannot

There are three levels, and they get mixed up constantly. The first is the technology: did the device run, did the content run, how often, how long. That is hard measurement; the player logs it itself. The second is the opportunity: how many people were within range, how many could have looked. That can be estimated, with honest imprecision. The third is the effect: did the screen change anything, in sales, in atmosphere, in the number of queries. That can only be grasped by comparison, never as an absolute figure.

Anyone who claims to tell you exactly how many people saw a slide is selling an extrapolation as a measurement. That is not dishonest as long as it is called that: footfall times a visibility factor times the share of playout time gives an estimate you can plan with, but not a count.

And some things simply cannot be measured. Whether somebody entered the shop because of the window, whether the waiting room feels calmer – there is no sensor for that, only the eyes of the staff who stand there every day.

The playout log

The most reliable figure in any signage system is also the least spectacular: the playout log, known in the trade as proof of play. Every player records which file it showed, when and for how long, and reports it back. The result is a list that answers three questions: what ran, when, where.

On your own surfaces this is a control instrument. You can see whether the promotion really started on Monday, whether the Christmas slide ran on past New Year and whether the screen in the basement actually played or only claims to be switched on. In our advertising network the same log is the billing basis: anyone booking at third-party sites pays for playouts, and those have to be provable.

On third-party surfaces, watch three points. Is billing per site or as a flat rate across a network? What happens to playouts that did not run because of an outage? And do you get the log as a verifiable file or only as a pretty summary? That last answer says a lot about the provider.

Counting on site

If you want to know how many people come past at all, you need a source on site. The simplest is the counter at the door, which many shops already have; it delivers daily curves and weekly patterns and costs no data protection debate.

Anonymous sensors go further: small devices that count people in the field of view without storing images. They only output numbers – passers-by, people facing the screen, average dwell time. Gaze detection measures whether a face was turned towards the screen; thermal sensors count bodies rather than faces and work in half-light too. What is permitted and how to handle the duty to inform and anonymisation is covered in the chapter on network, power and security.

The shop till is underrated. It is the most honest data source in the building: it knows what was actually bought, in what quantity, at what hour. For most small businesses an analysis by item and period says more than any sensor on the ceiling – and nobody has to hang up a camera for it.

Comparison instead of gut feeling

Effect shows up in comparison. A single figure says nothing – two hundred lunch specials sold is a lot or a little, depending on what came before.

The cleanest route is comparing two branches: two similar sites, the same item, the same week, screen advertising in only one. If you only have one site, compare periods – two weeks with, two without, alternating, so weather and holidays average out. And rotate the item being promoted: if the effect appears with three items, it was not the item but the surface.

An example from a furniture store: an armchair had been in row three for months and sold moderately. For two weeks it ran on the screens in the entrance, then two weeks not, then two weeks again. The till figures per period showed a clear pattern, and a hunch turned into a decision about which pieces go on the screens in future.

The bridge into the digital world

A screen ends at the pane of glass. Anyone who wants to know whether somebody then acted builds a bridge to the phone – usually a QR code. It is often used wrongly: too small, shown too briefly, too low down, with a destination that is unreadable on a phone.

• Size: at least one tenth of the viewing distance. From three metres, therefore no smaller than thirty centimetres.
• Dwell time: ten to fifteen seconds – the phone has to be fished out first.
• Placement: at chest height, not at the top edge of the image, with a calm margin around it.
• Destination: a lean page for the phone, not the home page, with its own short link per site.

Equally useful are promotional codes quoted at the till, and signing in to the guest wifi when the screen points to it. Also look at the tools you already have: searches for your name during and after a campaign, views and route clicks in your Google business profile. Those curves are not proof, but they move reliably along with everything else.

Key figures that work in practice

You do not need twenty key figures. Five or six that somebody actually looks at are worth more than a report nobody opens.

Note for every figure who looks at it and what happens when it tips; a figure without an owner is decoration. And do not add anything up into an overall score – a score built from six figures says nothing any more about what to do.

The monthly report and the underrated figure

Once a month, twenty minutes: availability, playout, content age, effect. Four blocks, one page. Decisions follow every time, and they belong on the same page. If a site failed three times, a replacement unit goes into the store or the connection goes on the test bench. If a slide has been running for five months, it gets replaced or deliberately marked as permanent content. If a promotion produces no response, change the message first, not the hardware.

The most underrated figure is availability. Design gets discussed endlessly, outages rarely – yet a black screen costs more reputation than a mediocre slide. The mediocre slide goes unnoticed. A dark device in the shop window, though, is read: nobody here is looking after anything. And an installation still running last winter's promotion in June says more about your business than you would like.

That is why availability stands at the top of our report, ahead of all the effect figures. Anyone who first makes sure that every surface shows something current during every opening hour can then calmly turn to the two seconds this book is about.

Measure against a goal you wrote down beforehand – and first of all check whether the screen was running at all.

On a Tuesday morning a woman stands at the drinks counter of a gym, waiting for her shake. Eighty seconds with nothing to do. Above the counter a screen is running: first a note about the evening class, then a spot for a garage in the next village, then the weather. She looks, because there is nothing better to look at. Those seconds are exactly the goods a digital advertising network trades in.

Your own surface, someone else's surface

A screen belongs either to you or to somebody else. That sounds banal, but it is the most important distinction in this chapter: it determines what you are allowed to show, who maintains the content and who sends whom an invoice.

On a surface of your own – in the shop window, in the branch, in the waiting room – you are the host. You decide the content and can turn it upside down tomorrow morning. In return your reach is exactly as large as your own flow of customers. Anyone who does not walk past your building sees nothing.

On somebody else's surface you buy your way into a flow of people that somebody else generates. You reach people who do not know your business, and that is the whole point. In return you have seconds rather than minutes and you follow other people's formats and deadlines.

Most businesses that take this seriously do both: their own surfaces for depth, other people's for breadth. How to fill your own surfaces is covered in the chapters on hardware and content. This chapter is about what happens outside.

Where DOOH happens in Switzerland

Digital out of home, DOOH for short, means nothing more than digital advertising beyond your own four walls. Not on the phone, but out and about. The term comes from the poster world, and DOOH behaves the same way – except that the surface can change while the person is standing in front of it.

In Switzerland you find such surfaces almost everywhere people gather or linger:

• Railway stations, platforms, bus and tram stops
• Shopping centres, arcades, entrances of large retail chains
• Petrol station shops and their checkout area
• Gyms: changing room, weights area, drinks counter
• Medical practices, physiotherapy, hospital waiting areas
• Takeaways, snack bars, bakeries with standing tables
• Sports facilities, indoor pools, clubhouses

The networks differ greatly. Transport networks deliver many fleeting contacts in a short time. Networks in gyms, practices and neighbourhood shops deliver fewer, but longer and calmer ones. Anyone advertising a regional trade business rarely needs the main station.

The language of media planning

Anyone reading a DOOH quotation for the first time stumbles over terms that sound similar and mean different things.

What matters is the relationship between the middle three. A sixty-second loop with six ten-second creatives gives each one a sixth of the time. Add a seventh and your share drops without anything changing in your booking. So always ask how long the loop is and how many creatives fit into it.

Programmatic booking merely means those slots are allocated via a trading platform rather than over the phone. For small, regional campaigns the direct route through the network operator is usually simpler.

Why waiting is so valuable

During installations I have spent a lot of time watching people who are waiting. For the train, for the coffee, for the doctor, for the free machine in the weights room. Waiting is a peculiar state: the mind is awake, the hands are empty, and the eye is looking for something to settle on.

That is exactly where the difference lies between a surface at a thoroughfare and one at a waiting place. At the thoroughfare you are fighting for two seconds of a hurrying eye. At the waiting place you may get the whole loop, and twice over. You are allowed to tell more, add a second message, even show something that requires a moment's thought.

That only applies as long as the screen hangs in the field of view. A display behind the backs of the people waiting is expensive wall cladding. For every site offered, check where people actually look: at the counter, at the departure board, at the door. That is where the surface belongs.

What makes a good creative

A DOOH creative is not a small television spot. It has no sound, no title sequence and no audience that stays seated. What works is surprisingly strict:

• Think silent. Anything that would have to be heard must be readable.
• Three seconds as the measure. Hold a sheet over the draft, count to three, look, cover it again. What stayed with you?
• One message. Not the offer and the opening hours and the new branch and the apprenticeship.
• The brand early. A logo only at the end means half the audience never sees it.
• Movement sparingly. One moving element draws the eye, five scatter it.

On the QR code, a clear position: at passing places it is pointless. Nobody stops, pulls out their phone and scans while the train pulls in. At waiting places, on the other hand, it is worthwhile, because the phone is in hand anyway. Then make it big enough, leave it up long enough and say what comes after the scan.

Planning a campaign

A DOOH campaign can be sketched out in a good hour if you go in order.

Start with the goal, in one sentence. Building awareness in a region, drawing visitors to an event, finding apprentices – those are four different campaigns, even if the logo stays the same.

Then the target audience, and from that the choice of sites, not the other way round. Anyone looking for apprentices is better served in sports facilities than in a waiting room.

Then the period and the daypart. A lunch offer belongs between ten and half past twelve, an evening event the other way round.

Plan creative variants from the start. Two or three motifs keep the campaign fresh and allow you to replace the weaker one after a week.

Only then come production and formats: resolution, portrait or landscape, file type, spot length. Every network has its specification sheet, and the approval deadlines are meant seriously – there are often several working days between delivery and first playout. Last comes measurement: what will you look at afterwards so that you are wiser next time?

Marketing your own surfaces

Operators of gyms and shops regularly ask me the reverse question: can I show other people's advertising on my screen and earn something from it?

It is worthwhile when three things come together: enough footfall. Enough dwell time, meaning real waiting situations rather than mere passing through. And an environment that suits possible advertisers – a gym for nutrition, a practice for preventive care.

Billing usually works in one of three ways:

• by time: a fixed amount for a booking period, regardless of footfall
• by contacts: the estimated number of visual contacts is charged
• by revenue: you receive a share of what the surface earns

Legally, three points need clarifying: does your lease permit third-party advertising? Does the surface need an advertising permit from the municipality? And how do you handle sensors for measuring contacts – the requirements of the revised data protection act apply as soon as faces are captured.

Going it alone is rarely worth it: finding advertisers, checking creatives and issuing invoices is a profession of its own. Anyone with one or two surfaces is better off joining an existing network.

An amplifier, not a lone fighter

DOOH almost never works alone. It makes known what gets deepened elsewhere. Somebody who has seen the name of a garage three times at the gym will click weeks later in the search engine on that entry rather than on the unknown one next to it. That is the contribution – not the direct sale.

That is why the combination works better than any channel on its own. Poster and DOOH share the visual language. Radio supplies the sound the screen does not have. Social media takes over the storytelling at length. The search engine catches whoever looks for you later. Use the same image and the same sentence everywhere.

One network built entirely on waiting situations is our own. IMAGEMEDIA operates more than five thousand surfaces at over a thousand sites in German-speaking Switzerland, mostly in gyms – where people stand between two exercises or have time in the changing room. The loops are longer than at a railway station, and regional businesses can choose precisely which municipalities they are visible in. Whether this network or another one fits is decided not by the surfaces but by the people in front of them.

On your own surfaces you have time; on other people's you are buying someone else's attention – plan the two differently.

Stand in the lunchtime queue at a takeaway counter and watch not the menu but the people. Almost everyone looks up as soon as they join the queue and reads while they wait. Anyone who reaches the front and only then starts deciding has not read the menu or could not read it. That is where it is decided whether a menu board does its job: not in the design, but in the four metres before it.

The most important surface in the place

No other screen is looked at as long and as attentively as the menu above the counter. Guests in the queue have nothing else to do: they read not for two seconds but for forty – and make a purchasing decision while they do.

That reverses the usual rules. A shop-window display has to get a single message across in two seconds; a menu board may be dense: prices, categories, side dishes, notices. What it must not do is change while somebody is reading. A board that flips every eight seconds forces the guest to wait for their page to come round again – that annoys people more than any ugly typeface.

Still, not every establishment needs a board. A restaurant with a fixed menu and a weekly special on a blackboard does excellently with chalk. The screen pays off where things change often or where many people wait: changing daily specials, seasonal promotions, several branches with the same menu, takeaway with a queue. In most businesses both end up existing – the board for the decision in the queue, the printed menu at the table for everything after that.

Legibility in the queue

The most common ailment of menu boards is called too small and too much. As a working rule we reckon on a cap height – the height of the capital letters – of roughly one hundred and fiftieth of the viewing distance.

The price column sits on the right and flush underneath, with the same number of decimal places – nothing reads more restlessly than a column where the figures dance. Set descriptions smaller than the product name, but never below half its size. How type and contrast work at a distance is covered in the chapter on content.

How a menu board is built

A good board reads like a well-organised counter: it begins top left and ends bottom right. If the menu does not fit on one surface, take two or three screens side by side and divide them firmly: hot food on the left, drinks in the middle, desserts on the right. Fixed places beat any rotation.

This structure has proved itself:

• three to five categories, set apart by a colour block or a rule, not by type size alone
• the best-selling items at the top, not the newest ones
• one single highlight per surface: the dish of the day or the promotion
• side dishes, sizes and surcharges as one line under the category rather than per item

Pictures sell, but they cost space and calm. Two or three per surface is enough, only for items where appearance decides – burgers, bowls, cakes. For drinks, text is enough. And they have to come from your own product: a purchased image that looks different from what goes over the counter is a disappointment waiting to happen.

The day in four menus

Here lies the advantage paper does not have. The same surface shows coffee and croissants at seven, the lunch offer at eleven, cakes at three and the aperitif from five. No handling, no forgotten menu change, no argument at eleven about breakfast.

Set the switchover to the kitchen's processes, not to the full hour. If the menu changes at twelve exactly, half the queue is standing in front of an offer the kitchen is not serving yet. Put the change ten minutes earlier, and make the transition soft.

The second part is the word sold out. Guests forgive a sold-out dish easily if they see it on the menu, and badly if they hear it at the counter after four minutes. Give the staff a way to grey out an item with one action – a tablet at the till, a list, a tap. Greyed out and struck through is better than gone: the guest sees that the dish exists, just not any more today.

Allergens, origin and price display

In open service – where food goes over the counter unpackaged – the Swiss ordinance on foodstuffs and utility articles and the ordinance on food information apply. For the menu above the counter that means three things.

Allergens: the information about ingredients subject to declaration has to reach the guest before purchase. Verbal information from staff is permitted – but then a written notice pointing to it has to be clearly visible. Anyone displaying allergens works with abbreviations after the product name and a legend at the foot of the surface.

Origin: for meat and fish it belongs in the product line or in a footer that stays permanently and does not rotate with the rest.

Price disclosure: what is shown is the price actually payable, including VAT. A price that only appears in one of three rotating views is not a clearly visible disclosure. Settle doubtful cases with the cantonal food inspectorate before the inspectorate comes to you.

Till, stock management and who maintains what

The appeal is obvious: the items are already in the till system, with name, price and availability. But this is exactly where the errors arise that nobody understands later.

What should come from the till and what should not:

• Prices: absolutely from the till. Two places for prices mean two different prices sooner or later.
• Item names: from the till, but with a second field for display. Internally it is called SDW-LG-VEG; on the menu it is «Sandwich large, vegetarian».
• Availability: from stock management, provided stock levels are genuinely maintained. Otherwise the tablet at the counter is better.
• Order and design: never from the till. Its merchandise groups are sorted for accounting, not for appetite.

Set down on half a page who maintains which field. The failures are always the same: an item gets renamed in the till and becomes cryptic on the board; the interface quietly stops working after a till update. That is why every integration needs a rule for the case where no data arrives: then the last valid menu stays up.

Takeaway, drive-through and the order number

As soon as the order is placed, the screen's job changes: it is no longer about selling but about calm in the room. A display listing order numbers in two columns – in preparation and ready – saves staff from calling out and guests from crowding at the hatch. The numbers have to be legible from every corner of the waiting area, so larger than anything on the menu.

An honestly stated waiting time works better than any apology. If your till system supplies an estimate, show it and round up. Somebody expecting fifteen minutes who gets their food after twelve is satisfied; the other way round, not.

For the drive-through, three things are added. The guest reads from the vehicle, often against the light: the display needs at least around 2500 candela per square metre, anti-glare protective glass and a sun shield. It stands outside, so it belongs in a housing with a suitable IP rating and with heating. And the menu has to be shorter than indoors: four to six items, large type, no descriptions.

Technology between fryer and counter

Proximity to the kitchen is an imposition on electronics. Grease settles as a film on glass and housing, steam carries it right up to the ceiling, and above a counter with a salamander it gets hotter than any data sheet allows for. Check the permissible operating temperature before you fix the mounting position, and leave air behind the screen: a display that cannot shed its heat throttles back or switches off.

What has proved itself:

• a professional display for 16/7 operation rather than a television, closed front, fanless construction
• mounting outside the steam plume of the fryer and the hob
• a bottom edge around 2 metres above the floor, so the queue does not block the view
• cleaning with a soft cloth and a mild agent, never with degreaser on the anti-glare coating
• the power supply and player outside the damp zone, in a ventilated cabinet

The critical light source is rarely the ceiling light but the window opposite. Before installation, stand where the guest stands and look at the planned surface – in the morning and in the late afternoon. More on this in the chapter on location.

A menu board gets forty seconds of undivided attention – type that is too small and too many items throw it away.

One November evening I arrived at half past ten at a hotel in Graubünden. In the lobby stood a totem, neatly mounted, good picture, welcoming the participants of a seminar that had finished the day before. At reception the young woman apologised: normally the front desk takes care of it in the morning, and today had been busy. That is exactly the situation in hospitality. The technology works, the people have guests in front of them, and the screen is only as good as the work it creates for nobody.

The first few metres in the building

Whoever walks in is looking for just one thing in the first few seconds: confirmation of being in the right place. That does not take much. A screen in the lobby carrying the name of the house, listing the day's events with room and start time and showing reception hours settles ninety per cent of the questions otherwise asked at the desk.

What has proved itself in reception areas:

• A greeting with the company or house name, for groups with the name of the event
• The day's overview: event, room, time, directions to the right wing
• Weather, mountain weather or snow report, where it suits the house
• The next departures of bus, train or boat from the stop outside the door
• Operational notices: breakfast times, spa, building work in the house, emergency exit

Restraint here is not a style but a strategy. A reception is not an advertising space. As soon as screens in the entrance show third-party advertising, they lose their role as signposts. Your own offers may appear, but as a note rather than an advertisement: the terrace is open, the restaurant takes reservations.

Door signs outside the seminar rooms

Outside meeting and seminar rooms, a small display replaces the paper signs somebody has to print and clip on every morning. It shows the room name, the current booking, the title of the event and the next free slot. The data comes straight from the calendar system, usually via the room mailboxes in Microsoft 365 or Google Workspace.

Three things decide how useful it is. First, colour at a distance: green and red at the edge of the sign answer the question «free or occupied» from five metres without anybody reading the text. Second, on-the-spot booking. A button for «occupy the room for thirty minutes» and another that releases an unclaimed reservation after ten minutes free up more capacity in busy buildings than any additional room. Third, calm. A door sign must not flash, must not beep and must not glow at night – it hangs in the corridor, often next to bedrooms.

We almost always solve the power supply with PoE: one network cable carrying data and power, no socket beside the door, no trunking in the marble.

The television in the room

Hotel TV is the only screen in the building the guest operates alone and at leisure. It should work in this order: immediately understandable, then useful, informative only last. The welcome screen names the guest and the key details of the stay, after which a plain menu leads onwards.

What a room television should be able to do:

• A welcome greeting with name, room number and departure date, taken from the hotel software
• House information: breakfast, spa, restaurant times, wifi access, emergency numbers
• A television programme in a channel list that suits the guest profile
• Streaming via screen mirroring from their own device or by signing in to the apps
• View the room bill, set a wake-up call, request a late checkout
• Language switching that changes the entire menu at once

With streaming, the delicate point is not the technology but the accounts. A guest signs in to an app, departs and stays signed in; the next one sees somebody else's profiles and can order. That is why checkout has to include automatic sign-out from all services and a reset of the device – triggered by the hotel software, not by housekeeping. Under the revised data protection act, record which guest data reaches the television and how long it stays there.

Hospitality device or living-room television

At the DIY store there is a television with the same diagonal, and it looks the same. The difference only shows up in operation, and it shows up in every room simultaneously.

Cloning is the practical heart of it. You set up one device completely, save the profile and push it to all the other rooms – with eighty rooms, that is the difference between an afternoon and a week. And the volume limit prevents the most common complaint in the house: the neighbour watching a film at midnight.

The network behind it

A hotel with a hundred rooms operates a hundred devices that load content and distribute programmes. We put room televisions, door signs and lobby screens on their own VLAN, separated from the guest wifi and the administrative network. That way guests never reach the control system, and an overloaded guest wifi in the evening does not confuse the door signs.

What has to be settled before the first installation:

• A network socket in every room behind the television, not beside the door
• A separate VLAN for signage and hotel TV, access only from the administrative network
• Bandwidth per room for streaming, plus an upper limit per device
• The television signal as IP distribution over the same network rather than over coaxial cable
• Integration with the hotel software for name, room, departure and bill
• Switching times and standby, so that only what has to run runs at night

Distributing channels over IP has largely replaced the old coaxial cabling. It saves the second cable run during a refit and makes rooms easy to retrofit, but it assumes a properly planned network. Picture dropouts in the room are, to the guest, a shortcoming of the house, not of the network.

Waiting without being bored

Waiting areas are everywhere: at the dentist, at the residents' registration office, at the garage, in a car dealership showroom. Anyone sitting there has one question in mind: how much longer? Everything that answers that question gets read. Everything else is trimming.

That is why the queue system comes before the programme. A visible number, the current position and an honest statement of the waiting time take the tension out of the situation. In one municipal administration we put the queue number large on the left and the information small on the right; afterwards hardly anybody came to the counter to ask whether they had been forgotten. The rest of the surface may explain: services few people know about, how a treatment proceeds, opening hours over the holidays.

On sound, a clear position: in waiting areas it stays off. People sit there involuntarily and sometimes tense, and they cannot escape the noise. Films run silently with on-screen text, and where sound is necessary – a name called out in a dealership – a short signal tone is enough. If music plays anyway, it has to be registered with SUISA; the tariff applies to a screen in a waiting area too.

Who maintains what

In hospitality no installation fails on the technology but on the duty roster. Reception changes, the season changes, and whatever cannot be done in five minutes between two arrivals gets left. That is why we let as much as possible come from the calendar and the hotel software.

Two rules carry the operation through the year. First, the change of season as an appointment in the calendar: winter and summer versions are built once and then simply switched over. Second, the languages. German and English are compulsory, French depending on the guest profile, and translation is done by people who speak the language. A clumsy greeting in the guest's mother tongue is worse than a clean one in English.

In hospitality the winning screen is the one that answers questions before they reach the front desk – and creates work for no one.

I sat in a meeting room with a very large screen and six people all looking at their watches. The presenter had a laptop without the right connector, the adapter was on another floor, and the colleague joining remotely heard the room only as a distant rushing sound. After nine minutes the picture came up. No device in that room was bad – nobody had simply answered the question of how a meeting begins.

Why meetings fail on technology

The faults have stayed the same over the years. They happen before the first word is spoken, and almost never in the screen itself.

• Connections: the laptop has a different plug from the cable on the table, and the adapter has vanished.
• Sign-in: the room asks for an account whose password nobody knows.
• Sound: the picture arrives, the sound does not, because the laptop has switched to its own speaker.
• State: whoever used the room last left it half-way through something, and nobody knows which button leads back.
• Guests: an external visitor cannot show anything, because there is no in-house account.

From which follows the most important rule for any room: a meeting has to start in two moves. Plugging in a cable or pressing a button — that is the limit. We do not judge a room by its diagonal, but by the time it takes to reach the first picture.

Room size, picture size, legibility

The most common planning mistake is a screen that is too small: it looks enormous in an empty room and turns out too small once the room is full. As a rule of thumb, the furthest seat should be no more than four to six times the picture height away — four for anyone showing tables and plans, six for anyone showing slides and faces.

On choosing between a video wall and a projector: a projector needs blackout and a light source that has to be serviced. An LED wall or a large display stays legible in daylight and switches on instantly — as soon as a room is used daily, the screen wins. Pixel pitch and viewing distance are covered in the chapter on hardware.

Fixed installation or your own laptop

Two worlds share the market, and both have their place. A permanently fitted room — Teams Rooms or Zoom Rooms — has its own computer, a keypad on the table and a calendar. The meeting appears as a button; one press starts the call with the room camera and the room microphones. That is the most reliable sequence, but it ties the room to one system.

The other route is BYOD: the laptop people bring stays the computer, and the room supplies picture, sound and camera. By cable or wirelessly, with Barco ClickShare for example, the screen content reaches the wall, while camera and microphones announce themselves to the laptop as accessories. This works with every conferencing service and with every guest in the building.

• Permanently fitted: fastest start, the same operation in every room, clear responsibility, but tied to one supplier.
• BYOD: open to any service and any external visitor, cheaper to install, but dependent on the user's own device.
• Both together: a fixed room computer, and beside it a cable and a transmitter for guests.

For rooms with external guests we recommend the third option; for rooms used only by the team, the first.

Sound and camera are the real quality

People dialling in will forgive a mediocre picture, never poor sound. Speech intelligibility is not created in the microphone but in the room: a meeting room with a glass wall, a stone floor and a long table echoes, and no microphone takes reverberation back out afterwards.

The order is therefore always the same: acoustics first, then microphones, then the camera. Acoustics usually means a few square metres of absorbent surface on the ceiling and the rear wall, a carpet or a curtain in front of the glass façade — unspectacular and effective at once. Only then the microphones: a bar below the screen covers a short table, two table microphones a long one, a ceiling microphone the whole room — the last only in treated rooms, otherwise it mostly picks up the ventilation.

With the camera, the angle matters more than the resolution. It belongs above or below the screen, never in a corner, or those dialling in see nothing but profiles. Automatic framing that zooms in on whoever is speaking is reliable today. And one last point: the people in the room have to see the people dialling in — a second screen just for faces pays off in every hybrid room.

Controls that overwhelm nobody

The best installation is the one nobody talks about. You get there with three decisions. First: one place to operate it, not three — a keypad on the table, and the remote controls disappear into the drawer. Second: labels in the language of the house. "Laptop", "Conference", "Everything off" say more than "HDMI 2" and "Input Select".

Third: a standard state. Every room returns to it by itself after the meeting — home screen, medium volume, camera on the wide shot, no one else's sign-in still active. We set a timer for this: if no signal is detected for twenty minutes, the room falls back. It sounds like a detail and saves hundreds of calls over a year.

On the table the rule is: as few cables as possible, but the right ones. One cable carrying picture, sound, network and charging power through the same plug covers most laptops; a second beside it covers the older ones. The connection box belongs in the table, so the cables disappear downwards instead of hanging over the edge.

Cables, connection panel, power, mounting

What happens behind the wall decides whether a room is still usable in five years. Plan conduits generously: every additional conduit is a small effort during construction and a building site afterwards.

What we allow for in every room:

• a conduit from the table to the display wall, a second one to the ceiling for camera or microphone
• a power socket directly behind the screen, plus a switched circuit for the system
• a network socket behind the screen and at the ceiling, with PoE for camera and microphone
• HDMI lines with spare capacity, as a fibre-optic version over long distances
• control lines for RS-232 or CEC, so that one button switches screen and source together
• a VESA mount matched to the wall; on plasterboard, a backing plate fixed to the studs

Height matters when mounting: a screen in a meeting room hangs lower than most people expect — the centre of the picture sits roughly at the eye level of a seated person. Projectors and loudspeakers at the ceiling belong in the load-bearing structure, not in the suspended ceiling.

Door sign and room booking as an addition

A well-equipped room is of little use if nobody knows whether it is free. The small display beside the door closes that gap and creates no work, because it draws its data from the same calendar as the room: free or busy, readable from five metres away, the title of the current meeting, the next free slot, a button for spontaneous use.

The real gain lies in releasing bookings nobody turned up for: booked, never used, never cancelled. When the sign releases itself after ten minutes without confirmation, capacity appears that nobody had seen before.

Take the occupancy figures that accumulate seriously: after a quarter they show which room size is missing — usually not the large rooms, but the small ones for two to four people. Door signs are covered in more detail in the chapter on hotels and reception.

Handover to IT and operation

A room is built by tradespeople and run by IT. Most is lost between those two moments, which is why every project includes a handover that is more than a folder of manuals.

What IT needs to know before installation and receives afterwards:

• network permissions: which addresses and ports the devices need to reach outside
• device accounts for the room computer and room mailbox, with passwords that do not expire
• a separate VLAN for the room technology, kept apart from the workplace network
• responsibility for updates to the room system, the screen and the control
• access to remote monitoring, with an alert when a room goes offline
• one sheet per room listing devices, lines and addresses

Standardisation is the biggest lever. Anyone building five rooms builds them alike: the same operation, the same labels, the same layout on the table. Training then takes ten minutes, and a replacement device fits anywhere. We prefer to train twice — at handover and after four weeks, once the real questions have come up.

A meeting room is good when the meeting starts in two moves and everyone dialling in understands every word.

In the foyer of a cantonal hospital I helped a woman who had walked past the same screen three times. It showed a handsome plan of the building, in colour, every floor – except that she was not on it. No dot saying: you are here. She was looking for dermatology, found a floor plan and went back to reception. Wayfinding rarely fails because of the technology. It fails because somebody drew a plan instead of answering a question.

The rules of wayfinding

People do not read a building, they make decisions. At the entrance: left or right. At the lift: which floor. Out of the lift: which corridor. Wayfinding means standing at exactly those points and answering exactly the question that arises there — not earlier, not later, and not all at once.

Five rules carry any installation, whether made of sheet metal or glass:

• Decision points first: every junction gets an answer, and in between there may be quiet.
• Respect the line of sight: the screen hangs where the eye falls anyway while walking, before the turn-off and not after it.
• Order destinations by hierarchy: wing and floor first, then department, then room. Nobody reads more than seven destinations on one level.
• One word for one destination: if reception says "Radiology", the screen must not show "Imaging".
• Pictograms as an anchor, text as proof: the eye finds the symbol, the word confirms it.

The most common mistake is the beautiful map. A floor plan without a you-are-here point, without alignment to the direction of travel and without a drawn route is a drawing for architects, not help for visitors.

Screen or sign

In operation, a sign is unbeatably frugal: no power, no network, no maintenance. A screen earns its place only where the information changes. That distinction saves devices in every project, and we regularly argue for it against the client's first wish.

Arguments for the screen:

• changing occupancy of halls, meeting rooms and training rooms
• events with date, time and room
• consultation hours and attendance times that look different every day
• building work, moves and diversions inside the building
• several languages that take turns instead of standing side by side

Stick with the sign for everything permanent that has to work when in doubt. Emergency exits and escape routes belong on illuminated rescue signs and never on a surface that can fail. The same goes for toilets, stairwells, the floor number in the lift, door numbers and everything in rooms without a power supply.

The rule of thumb: what does not change within a year gets written. What changes within a week gets displayed.

Touch kiosk: more than a big screen

As soon as visitors may search for themselves, a display becomes a device that is operated. With that come questions that play no part in a display-only screen.

Operating height first. Controls belong in a zone that seated and standing people can reach — roughly 85 to 120 centimetres above the floor, with the most important buttons in the lower third of the picture. A portrait-format kiosk that carries its menu at the top is unusable from a wheelchair.

Then the search. An on-screen keyboard with suggestions from the second letter onwards finds "Müller" and "Mueller", "ENT" and "ear, nose and throat". Alphabetical directories only help those who already know the name.

The result is not the room number but the route: a map with a you-are-here point, a drawn line, a change of floor as a step of its own, plus the walking time. Anyone who wants to take the route with them gets it on their phone via a QR code; a printer in the foyer is the second option, but it demands paper, servicing and someone to refill it.

Settle hygiene and cleaning beforehand: a front pane, daily cleaning written into the cleaning schedule, and a device that returns to the home page by itself after two minutes of inactivity.

Five buildings, five tasks

The same technology solves a different task in every building. In the municipal offices it is about counters and opening hours, in the hospital about arriving calmly, at a trade fair about speed.

In a hospital, one extra thought is worth it: whoever is standing there is rarely relaxed. Large type, little movement, no advertising beside the route to oncology. At a trade fair the opposite applies — there speed and overview count, and a hall plan may be large and colourful.

Where the data comes from and who maintains it

Wayfinding is only as good as the directory behind it, and directories go out of date quietly. That is why, before installation, we establish which system holds the truth — and we do so for each item separately.

The usual sources:

• room and occupancy planning for halls, training rooms and meeting rooms
• departmental calendars for events and consultation hours
• the staff directory or internal phone book for names and rooms
• the tenant register held by the management for companies and floors
• the school's timetable software for rooms and cover lessons

Direction matters: data flows from the leading system to the screen, never the other way round and never maintained twice. As soon as someone keeps a list up to date in the signage software that already exists elsewhere, decay is guaranteed.

To that belongs a name on the organisation chart. Who enters the new tenant, who reports a department's move, who checks each quarter whether signs and screens still say the same thing? And define what appears when a source falls silent: the last valid list with a timestamp, not an error message. The chapter on software and operation goes into more detail.

Taking accessibility seriously

For people with a disability, orientation is not a comfort but the precondition for arriving at all. The Disability Equality Act requires publicly accessible buildings to make services reachable without outside help. Wayfinding is part of that.

What that means in practice:

• contrast: light text on a dark ground, no grey on grey, no type over restless images
• type size according to reading distance, judged from three metres and not at the desk
• operating height and enough space in front of the kiosk for a wheelchair to come close
• a read-aloud function or a headphone socket wherever the installation gives information
• plain language: short sentences, no officialese, one term per destination
• no flashing, no rapid changes, enough dwell time per page
• subtitles on videos, since the sound in a foyer is rarely on anyway

If you only want to check one thing: stand three metres away with your back to the screen, turn round and count how long it takes you to find your destination. Anything over five seconds is too complicated. For type sizes and contrasts in detail, the chapter on content takes it further.

Emergencies and safety

In an incident, every surface in the building becomes the surface everyone looks at. That is an opportunity: through the signage software an evacuation page can be pushed to all devices within seconds — a floor plan with the assembly point, a notice in several languages, calm instead of rumour.

The trap lies right beside it. A digital signage installation is not a safety system. Emergency exit luminaires, escape route markings, fire detection and voice alarm follow the cantonal fire safety regulations and run on their own power supply. Your screen may supplement these systems, never replace them: it depends on a network that will be switched off in an emergency.

In practice that means:

• the emergency page as a prepared template, not designed during the incident
• triggering from a defined position, with authorisation and a log
• coupling to the fire detection system only through a potential-free contact and in agreement with the fire safety authority
• a clear rule about who takes the display back down
• one test a year, together with the evacuation drill

Discuss this with the building's safety officer before you set it up. That half-hour saves an awkward discussion later on.

Wayfinding answers exactly one question at every junction – the screen shows what changes, the sign shows what stays.

In a joinery in Aargau the notice board hung next to the time clock. On it: last summer's holiday plan, two safety notices with dog-eared corners and a note about an event three weeks past. The owner told me he writes everything down but nobody reads it. I asked him where his people actually stand in the morning. The answer was the coffee machine. That is where a screen hangs today.

Why the notice does not get through

A notice demands that somebody stops, looks and reads. That is exactly what nobody does on the way to the machine. On top of that, a notice board makes everything equally important: the holiday plan hangs next to the staff meeting, next to the note about the broken coffee machine. Anyone who has read something out of date three times does not look the fourth time.

A screen changes nothing about this at first. It changes something as soon as it does three things paper cannot. It shows one after another instead of side by side, so always one thing only. It tidies up after itself, because every item carries an expiry date. And it stands where people are waiting anyway: at the coffee machine, in the changing room, at the time clock.

That waiting time is the real raw material. Two minutes at the machine is more attention than a circular ever gets. Which is why the two-second calculation from the first chapter does not apply here: in the break room, pages may stand longer and carry more figures. At the passage into the hall it applies again in full force.

Place by place

A plant has no customers in the building, but shifts, trades and routes. Every place has its own audience and its own dwell time, and therefore its own content.

Start with one place, not six. The break room is almost always the right first one: attention is greatest there and the damage smallest if the content is not yet right in the first weeks.

Content that lands in the business

What runs internally must not sound like a brochure. People in the building notice at once when a surface lectures them instead of informing them. A mixture of usefulness, operations and recognition has proved itself:

• shift plans, cover arrangements and last-minute changes
• the canteen menu with the dish of the day
• production figures: output, scrap, delivery reliability
• accident-free days, large and without comment
• faults and their current status, so nobody asks twice
• vacancies in the building, before they are advertised externally
• a welcome for new staff, with a picture and their role
• birthdays and service anniversaries, only with consent

The last point is not a formality. A date of birth is personal data under the revised Data Protection Act, and not everyone wants half the workforce to know their age. Ask once in writing, record the answer and respect a no without coming back to it.

Showing figures without monitoring individuals

Figures on a screen in the hall are the most effective and at the same time the most delicate element of an internal installation: a shift sees at once where it stands — and the same display quickly turns into performance monitoring.

For the presentation:

• at most three or four figures per page, large enough for ten metres' distance
• always the target value beside it, otherwise the figure says nothing
• a comparison with the previous day or the previous shift rather than a bare total
• use colour sparingly: green and red only where action is actually taken
• a figure nobody in the hall can influence does not belong on the wall

Legally and humanly the same rule applies: figures are shown per line, per machine or per shift, never per person. A display that makes the behaviour of individuals visible is a monitoring system for behavioural control, and the Labour Act and its ordinance set narrow limits on that. The Participation Act also gives the employee representatives a right to be heard. Bring the staff committee to the table before the first figure goes live. It costs one meeting and saves a year of mistrust.

Connecting data and starting small

The question always comes up the same way: does the machine have to talk to the screen? It does not, at least not at the start. Almost every internal installation we have accompanied began with a spreadsheet somebody updates on a Friday afternoon.

The path from simple to demanding:

• a spreadsheet on the company drive that the software reads every hour
• an ERP extract as a file, saved once per shift
• a view from the ticketing or maintenance system for faults
• an interface to production data capture for output and running times
• machine data straight from the controller, cleanly separated from the office network

The last point is a network topic, not a signage topic. The production network and the office world stay apart; the player fetches its data from a defined point and never writes back. How network, power and access are built is covered in the chapter on network and security.

Start with the spreadsheet. Once it is clear after three months which figure really gets looked at every day, you will also know which interface is worth having.

Technology that survives dust and forklifts

A device from the electronics shop does not survive a production hall for long. Dust settles in the fan, cutting fluid creeps into every opening, in winter the hall sits at ten degrees and in August far above that.

What we watch for on industrial surfaces:

• IP rating: IP54 against dust and splashes, IP65 and above in a wash bay or food production
• impact resistance to IK for surfaces near forklifts, plus a housing with safety glass
• check the permitted operating temperature, not only the storage temperature
• fanless devices where there is dust, closed housings with circulating air where there is no alternative
• brightness from around 700 candela per square metre in bright halls with roof lights
• vibration: mount on the wall or on a stand of its own, never on the machine
• cleaning in the cleaning schedule, with the agent approved by the manufacturer

Mounting at height is easily forgotten. A surface below the hall ceiling is quickly fitted and afterwards can only be serviced with a lift platform. Hang lower where you can, and plan access for maintenance at the same time.

Clarity and safety

In many plants, people from eight countries work the same shift. German is the company language, but not the language everyone reads in under time pressure. A text that a third of the workforce only half understands is not a notice but a risk.

What helps:

• picture before word: a photo of the right safety glasses says more than three lines
• standardised safety signs to ISO 7010, which mean the same thing everywhere
• short sentences in the active voice, one thought per line, no nesting
• language versions of the same page taking turns, rather than bilingual small print
• video sequences without sound, because nobody hears anything in the hall anyway

The same rule applies to safety communication as to wayfinding in the previous chapter: the screen reminds, it does not alarm. Protective equipment, conduct rules, what to do after a near miss, the assembly points — all of that may and should run, ideally in rotation so it does not become wallpaper. The alarm itself stays with the system built for it.

Who submits, who approves

An internal installation lives or dies by participation. If the content comes only from management, within two months the surface is a bulletin organ nobody looks at any more. If it comes from everywhere without rules, something will eventually end up on it that has no business being there.

The middle way is half a page of ground rules:

• Who may submit: every department, through a form or an internal address
• What is not shown: personnel matters, conflicts, third-party advertising, anything confidential
• Who approves: one named person with a deputy, within one working day
• How long an item runs: set the expiry date at submission

A surface stays alive through people, not through technology. A picture of the apprentices' project, the long-service colleague with her team, the photo of the new machining centre on delivery day: these items get retold, and the figure beside them gets read along the way. After six months, ask during the break what stuck. The answer says more than any analytics report.

Internal screens work where people are waiting – with few figures, clear pictures and names instead of announcements.

The manager of a furniture store called on a Thursday: she needed six screens in the entrance by the opening in fourteen days. We drove out. There was a socket meant for the Christmas lights, no network connection and no answer to the question of who would create the content. The screens went live six weeks after the opening. Not because of the technology – because of everything else.

Phase one: clarification

Before a device is chosen, six questions need answering — in writing, on one page, by the person who decides.

What is the goal? Not "digital signage", but: make the wait feel shorter, show the dish of the day, guide visitors through the building. Anyone who cannot state their goal in one sentence buys the wrong equipment.

Who is the audience? Customers, staff, passers-by? Each group needs different content and different locations.

Where exactly? Walk through the building and mark the spots with tape on the floor. It takes twenty minutes and prevents the most expensive mistakes.

What content already exists? Photos, logos, menus, opening hours, a till or booking system — whatever exists in structured form can later be displayed automatically.

Who runs it day to day? A person with a name, not "marketing".

And which systems are already there? Network and firewall, merchandise management, intranet, perhaps a screen from an earlier attempt. All of it influences what makes sense.

Phase two: concept

Now the answers become a plan the electrician can read too.

The location plan records for every position: place, size, format, mounting type, viewing direction, ambient brightness. A floor plan with numbered points is enough; the numbers stay with the project through to handover.

The content plan says what runs on each surface, how often it changes and where it comes from. It is the one projects skip most often and add back most expensively.

The choice of technology follows from both: size and brightness to suit the surroundings, 16/7 or 24/7 operation, separate player or built-in SoC, IP rating for outdoor positions. The basics are in the chapter on hardware.

Network and power are the underestimated half. Every position comes with the question of where the power comes from and whether the network can be reached by cable, PoE or radio. Radio is the fallback, not the choice.

Add a schedule with milestones and a list of everyone involved with phone numbers: electrician, building management, IT, marketing, and for outdoor surfaces the municipality. Whoever is missing here will be missing at the wrong moment.

Phase three: procurement and preparation

Between the order and the installation lies the phase in which a project either becomes calm or stays restless.

Delivery times set the hard rhythm. Standard screens are usually available quickly; special mounts, kiosks, outdoor housings and LED modules far less so. Order the slowest item first and build the schedule around it.

Pre-configuration happens in our workshop, not on the ladder. Players are set up, named, entered into the management system and loaded with a first piece of content; every box carries the number from the location plan. What remains on site is fixing, connecting, aligning.

A test build pays off from three similar positions onwards: one device on the table, all content played through, type sizes checked from the real distance.

In parallel, templates and first content take shape. An installation with nothing to show on installation day starts on a still image and is never properly started again. And schedule the training now, with a date.

Phase four: installation

Installation day is the day when all the preparation pays off or takes its revenge. Settled beforehand must be:

• Access: who unlocks, where do people park, where may material stand, is there a lift?
• Occupational safety: from what height is a lift platform needed, does an area have to be cordoned off, is an induction required?
• Opening hours: in shops and practices, installation happens before opening or after closing. That belongs in the planning, not in a discussion on the morning itself.
• Dust and noise: drilling into concrete produces both, and in practices, hotels and open-plan offices that matters. Vacuum at the drill hole, protective fleece on the floor, neighbours informed in advance.
• Cable routes: where does the cable run from the device to the socket — surface-mounted, in trunking or in the wall? That is where most time is lost on site.

At the end comes handover with a protocol: every position by number, picture running, alignment straight, cable routed, device visible in the management system, timer checked. Two signatures underneath — that sheet will later be the basis for any warranty question.

Phase five: commissioning and training

An installation does not go into service when it lights up, but when someone in the building can run it.

First establish who learns what. Usually three levels are needed: one person who designs and plans content; two or three who swap something day to day or report a fault; and one person with full rights who assigns access. The third is missing surprisingly often, and then everything stops as soon as someone leaves the company.

Training belongs at the devices, not in the meeting room, and rarely takes longer than two hours. Afterwards the trained person makes the first change themselves while we stand beside them. Nobody learns by watching.

To that belong a short manual with the five actions that are really needed, and an access list: who has which account, who deputises, where fault reports go.

We stay close through the first week. That is when the typical questions come: why is the picture cut off on the right, why does the weekly programme run on Sunday, why does the photo from the phone look blurred.

Phase six: operation

Operation is the longest phase and the only one that never finishes. Three things keep an installation alive.

First, the editorial plan. One sheet recording what changes when: the daily offer every day, the promotion weekly, seasonal images four times a year, contact details checked twice a year. A fixed date in the calendar is worth more than any concept. Installations do not die of technology, they die of indifference.

Second, service: remote monitoring that reports when a device stops responding, an agreed route for fault reports, a replacement device for critical positions and an annual visual check — dust in the fan, mount secure, picture straight, cables undamaged.

Third, extension. Every installation that works sparks ideas: another screen at the second entrance, a menu board, an outdoor surface. Extend with the same devices and the same software. An estate of five brands and three systems is the surest route to a standstill.

Who does what, and how long it takes

The most common cause of a stalled project is not technology but an empty line in this table.

A typical timeline, if nobody puts the brakes on:

Allow several extra weeks for special constructions and signage requiring a permit. And never set the go-live for opening day, but before it.

Brakes and questions

What delays projects is remarkably uniform: no power at the desired spot; a lease that ties structural work to the landlord's consent; heritage protection or a missing signage permit for surfaces facing outwards; delivery times for special parts; nobody who feels responsible for the content; IT approvals that sit for weeks. Almost all of it can be settled in the first week if you ask about it.

Ask a supplier before you sign:

• Who owns the software, and what happens to the content if we switch?
• How do we get a replacement device, and how long does it take?
• What exactly is included in maintenance and what is not?
• Who trains us, and how does follow-up training work?
• Can we look at an existing installation?

And prepare for these questions in return:

• Who decides, and who approves content?
• How many hours a month are available for upkeep?
• When are your busy times, and when may we install?

Anyone who brings these answers shortens the first phase from weeks to an afternoon.

Projects rarely fail on technology, but on power, approvals and the question of who will maintain the content.

A few years ago an optician called me: his new shop-window screen was faulty, it was showing nothing but black. I drove over; it was half past two on a July afternoon, and the unit had shut down because it was over fifty degrees behind the glass. Nothing was broken; the choice was wrong. Most of the faults we solve on the phone or up a ladder are not faults at all. They are decisions made six months earlier. Here are the twelve we meet most often.

Mistakes 1 and 2: the wrong device, the wrong place

Mistake 1: a television instead of a shop-window display.

• Symptom: in the morning, passers-by mostly see themselves; the picture looks milky and grey. On hot days the device shuts down.
• Cause: a television delivers 300 to 400 candela per square metre and is built for the living room, not for sun behind glass. There the temperature climbs far above the permitted 40 degrees. Add the warranty question: manufacturers exclude continuous commercial use for domestic appliances.
• Remedy: a display with at least 2500 cd/m², approved for 16/7 and with an operating temperature up to 50 degrees. How to determine the brightness is explained in the chapter on hardware.

Mistake 2: mounted too high.

• Symptom: the screen hangs above the shelving and nobody looks up.
• Cause: it was mounted where the wall was free, and the wall was free up high.
• Remedy: centre of the picture at eye level, around 1.50 to 1.60 metres above the floor for standing viewers, lower in a waiting room. If the device has to hang high, we tilt it five to ten degrees downwards and increase the type size by one step.

Mistakes 3 and 4: no network, no socket

Mistake 3: no network at the screen's location.

• Symptom: the installation shows content from the week before last, and nobody knows whether the device is running at all.
• Cause: the location was chosen for the window, not for the cabling. The WiFi reaches the shop door but not through the fire wall into the basement.
• Remedy: a network cable to the device while the ceiling or floor is still open. If that is impossible, a small router with its own SIM card for this installation. WiFi is the last choice, and then with an access point within sight of the player.

Mistake 4: no socket where the device is meant to go.

• Symptom: a white cable duct across the shop window or a power strip among the displayed goods.
• Cause: the electrical planning was finished before the screen became a topic.
• Remedy: the socket belongs behind the device, hidden in the area of the VESA mount, and in the floor for kiosks. Tell the electrician the spot before the interior fit-out begins.

Mistakes 5 and 6: too much text, wrong format

Mistake 5: too much text on one page.

• Symptom: bullet lists with eight points, a location map in small print. Nobody stops.
• Cause: the page was created at a desk, sixty centimetres from the eye, and there it looked good.
• Remedy: one thought per page, the core message in seven words at most. Check every page from where your customers stand. Whatever you cannot grasp from there in two seconds is too small or too much.

Mistake 6: wrong aspect ratio, resolution too low.

• Symptom: black bars left and right, distorted logos, a picture as if seen through frosted glass.
• Cause: an advertisement from a print layout or a square post from the web lands unchanged on a portrait-format screen.
• Remedy: a separate version for every format, 1920 by 1080 pixels for landscape, 1080 by 1920 for portrait. Supply images at the screen's pixel count, never scale up. Convert office slides and PDFs into an image or a video beforehand.

Mistakes 7 and 8: the rhythm and the sound

Mistake 7: the loop is too long or too short.

• Symptom: too long, and hardly anyone catches the most important message. Too short, and the same three pages flicker every half minute until the staff pull the plug.
• Cause: nobody measured how long somebody actually stands in that spot.
• Remedy: tie the length to the dwell time. In a shop window, 60 to 90 seconds is a good value; at the till, two to three minutes; in a waiting room, five to ten.

Mistake 8: sound where sound is a nuisance.

• Symptom: on the second day the sales assistant turns the sound off, and without the voice-over the film makes no sense.
• Cause: a corporate film was taken over exactly as it had been cut for the web.
• Remedy: in a sales area, a screen runs silent. Cut videos so they work without sound, with subtitles. Sound belongs where somebody stops voluntarily: a trade fair stand, a kiosk with a button, a directional speaker above a seat. And remember the rights: the SUISA tariff also applies to background music played from a screen.

Mistakes 9 and 10: nobody maintains, nobody watches

Mistake 9: nobody responsible for the content.

• Symptom: in February the Christmas promotion is still running.
• Cause: everyone was enthusiastic at the launch, but the minutes contained no name and no date.
• Remedy: one person with a name, a deputy, a fixed date in the calendar; twenty minutes on a Monday morning is enough. Give every campaign an expiry date and the installation will tidy itself up.

Mistake 10: no monitoring, nobody notices the black screen.

• Symptom: the device in the branch has been dark for eleven days. The manager heard about it from the neighbour, not from the system.
• Cause: whoever walks past it every day eventually stops seeing it, and whoever controls it sits somewhere else.
• Remedy: software that has every device report on itself: is the player online, is playback running, and is the screen really switched on via CEC or RS-232. Plus an email alert if a device goes silent for fifteen minutes. In our advertising network we see every outage on the same day.

Mistakes 11 and 12: the wrong order

Mistake 11: the permit considered only after installation.

• Symptom: four weeks after switch-on, a letter from the municipality arrives with a deadline and the word removal in it.
• Cause: a screen behind glass counts as advertising in many municipalities. In core zones, on protected façades and along roads, separate regulations apply, up to a ban on moving images or a requirement to switch off at night.
• Remedy: ask the building authority before ordering, in writing, with a photo of the façade. What belongs in a signage application is covered in the chapter on law and permits.

Mistake 12: the technology bought before the goal was clear.

• Symptom: a device sits in the storeroom, or it hangs and runs, but nobody can say what for.
• Cause: a good offer, a trade fair visit, a device that happened to be cheap.
• Remedy: write one sentence first: this screen is meant to achieve one specific thing, so that one specific thing happens. Then come the location, the content and the responsibility. The device comes last.

The quick diagnosis

When an installation plays up, it helps not to start unscrewing the device but first to name what you see. The table below is the order we follow when we arrive at a site.

Note what you checked and in what order. Next time you will be through in ten minutes.

How to recognise a good installation

Walk round your own installation once with this list, ideally in pairs and at a time when the place is busy. Whatever you cannot tick off is your next task.

• You can read the core message from the real viewing distance, without squinting and without stepping closer.
• The picture is rich even in sunshine, not grey, and the façade opposite is not reflected in the middle of it.
• The centre of the picture is at eye level, the device sits straight, the joint to the wall is clean.
• The loop matches the dwell time, and the most important message appears twice.
• No cable is visible, no power strip lies among the displayed goods.
• The installation runs silent, or the sound is wanted here and cleared legally.
• One person with a name maintains the content, and every campaign carries an expiry date.
• Every device reports on itself, and an outage is known on the same day.
• The permit exists in writing, including conditions on brightness and night-time operation.
• You can say in one sentence what this screen is for, and your staff can too.

Ten ticks, and not one of them expensive. Most of them cost a decision and twenty minutes.

Most faults are not faults at all, but decisions made six months earlier.

I am often asked what all this will look like in five years. Honestly, units we installed in 2017 are still on the same wall today, and the slides running on them follow the same rules as back then. Much of what was announced as a revolution never reached our workshop. Other things have quietly taken hold: units that adjust their own brightness. Menu boards that fill themselves from the till. Subtitles created in two minutes instead of two hours. This chapter sorts out what is really moving – and what stays as it is.

Power: what a surface really uses

The biggest lever on consumption is brightness, not the diagonal. A 55-inch indoor screen draws close to a hundred watts. The same device in a shop-window version at 2500 candela per square metre uses several times that, because the backlight does all the work. With LED walls, the picture content counts as well: a white surface uses considerably more than a dark image.

From that follow three adjustments that cost nothing but a setting:

• A brightness sensor instead of a fixed value. The device measures the ambient light in lux and adjusts. In the evening it runs at a fraction of its midday output, and the picture looks more pleasant into the bargain.
• Night dimming through the schedule. Dim from closing time, switch off after midnight, ramp up in the morning. Many municipalities require it as a condition anyway.
• A dark design. On LED walls, light text on a dark ground uses measurably less power than black text on white.

Using longer instead of buying new

Panels last longer than most people think. Manufacturers state 50,000 to 100,000 operating hours for the backlight before brightness has fallen by half. What reaches its end sooner is almost never the picture but the software: a device with a built-in player, an SoC device, eventually stops receiving updates.

That is why it pays, when buying, to look at separability. An external player can be swapped in five minutes while the display stays on the wall. Also ask about spare parts: power supply, mainboard, and for LED walls individual modules and receiver cards.

For the end of life, Switzerland has a clear system. Electrical devices are financed through the advance recycling fee and taken back by the SENS eRecycling and SWICO Recycling schemes. Return is free of charge, and dealers take devices back even without a new purchase. And consider a second life: a shop-window device that has grown too dim will still serve for years in a corridor.

Artificial intelligence that already takes work away

What has changed is not the screen but the route to the page. It is useful where there used to be manual work:

• Translating. The same page in German, French, Italian and English. A check by someone who speaks the language remains compulsory.
• Cropping images. A subject is cleanly cropped to landscape and portrait without the head being cut off.
• Text suggestions. A long announcement is boiled down to seven words, in three variants to choose from.
• Subtitles. The soundtrack yields a subtitle that you only have to correct. For silent screens this is the most important point on the list.

Add voice control at kiosks. It makes sense where hands are full or hygiene matters, and it helps people who read a screen poorly. In a station concourse or a gym with music it stays awkward. Plan it as an addition to the touchscreen, never as a replacement. Our yardstick is simple: the machine may suggest, a person has to approve.

Where artificial intelligence has no business

There are places where I deliberately switch off, and they have little to do with scepticism about technology.

Binding information does not belong in the hands of a machine. Prices, opening hours, allergens, emergency numbers, a municipality's deadlines: these values come from a checked source or from a person who stands behind them. Nor does uncontrolled generation belong on a public surface: whatever is created live has been read by nobody beforehand, and the screen in the window is a notice you are liable for.

The camera is delicate. Technically, age, gender or dwell time can be estimated. Legally you are then moving within the revised Data Protection Act, the nFADP, and practically within a question of trust. If at all, then with counting and no image storage, with a visible notice on the device, and with a purpose you can explain to a customer in one sentence. And one last point: no generated images of staff, rooms or products that do not exist in that form.

Installations that fill themselves

The clearest trend is unspectacular: less and less content is maintained by hand, more and more comes from a source that exists anyway. A baker shows croissants and coffee until ten o'clock, then the lunch offer. A sports shop brings up umbrellas when it rains. A furniture store takes a model out of the loop as soon as the till reports zero stock. Above all, this lowers the error rate, because a piece of information is only maintained in one place.

Every one of these sources needs the same protection: a fallback page for when it falls silent.

The surfaces themselves: thinner, finer, leaner

On the hardware side, less moves than the trade fair stands suggest, but three developments have arrived in practice.

LED walls are getting finer. Pixel pitches below a millimetre exist for indoor use, which brings the wall closer to the viewer without the dots becoming visible. Transparent versions behind shop-window glass keep the view into the shop clear, and curved ones follow a column.

Displays are getting thinner and lose their frames, which mainly helps installation. And then there is e-paper, the quiet alternative: price labels, direction signs, room signs, timetables. Such surfaces only draw power when they change, are excellently legible in sunlight and sometimes run for years on one battery. Colour is possible, the refresh stays slow, and there is no moving image. Where attention has to be won in two seconds, there is no way past a bright, moving surface. Where information merely has to be current, e-paper is often the wiser choice.

Accessibility becomes a requirement

One topic is growing noticeably, from two directions: from customers and from the legislator. In Switzerland the Disability Equality Act obliges public bodies above all; in Europe the European Accessibility Act has applied since 2025 and also covers self-service devices. Anyone buying a kiosk or a totem today should expect stricter requirements. The good news: what works for a person with impaired sight also works for the passer-by walking past in the rain.

• Contrast. Separate text and background clearly, no grey on grey, no type over restless images.
• Height and reach. Kiosk controls where someone in a wheelchair can also reach them.
• Subtitles. Every video with speech gets subtitles, and not only because of silent operation.
• Alternatives. A read-aloud function or a clearly legible notice beside it, wherever a screen is not operable by everyone.
• Flashing. Do without rapid changes and strong flashing; for some people they are a risk.

What stays, and a closing word

For all that is moving: the core of this book is untouched by it. A passer-by gives your screen two to three seconds, and in that time a thought forms or none does. It still comes down to the three things from the beginning: a goal you can state in one sentence, content looked after by someone with a name and a date in the calendar, and technology that suits the place rather than the other way round.

A personal word to close. Much of this book I did not learn at a desk, but on ladders, in shop windows in high summer and in conversations where a customer asked a question to which I had no good answer. I am grateful for both: to my team in Solothurn, who have made sure for years that an idea becomes an installation still running in its third winter. And to everyone who has entrusted us with their façade, their reception and their waiting room.

If while reading you thought of your own wall and are unsure whether your reasoning holds: ask somebody who installs such devices themselves, and ask early. And if you close the book and take away a single sentence, let it be this one: two seconds, one thought. Everything else is craft.

The technology is becoming leaner, finer and cleverer. The two seconds stay exactly as they are.

Digital signage is an honest discipline. An installation shows every single day whether anyone is looking after it. It does not forgive grand words, but it rewards small, regular attention: a current notice, a good image, an offer at the right moment.

If you have read this book and are still unsure whether a screen is worth it for you, that is not a bad sign. It means you are asking the right questions. Ask them of us. We will come by, look at the location, and tell you honestly if a printed poster is the better answer.

Philip Fiumi, Solothurn