"What size screen do I need?" is by far the question we are asked most when someone is organising a concert, a festival or a trade fair. And it makes sense: a giant LED screen is the most visible part of the whole set-up, the one that lets the audience in the back row experience the event just like the people in the front row. The bad news is that there is no single answer; the good news is that it is worked out from three very specific figures: the distance to the furthest spectator, the light in the venue and the content you are going to show. At Zenor Audiovisual we install modular LED screens at concerts and fairs all over Spain from our base in Albacete, and in this guide we explain how we size each installation so that you pay for neither one panel too many nor one too few.
What pixel pitch means and why distance rules
The pixel pitch is the distance in millimetres between the LEDs on the screen: a P2.9 has its pixels 2.9 mm apart, a P4.8 4.8 mm apart. The smaller the pitch, the more resolution there is in every square metre and the better it looks up close; the larger the pitch, the cheaper the surface becomes, but it needs distance for the eye to blend the dots into a continuous image. The quick rule we technicians use: the minimum viewing distance in metres is roughly equal to the pitch in millimetres. A P3.9 looks perfect from 4 metres onwards; for a trade-fair stand where the visitor walks past a metre away, you need a fine pitch. If you want to go deeper into how this technology works, the LED display article on Wikipedia has a complete technical explanation.
What screen size you need: the back-row rule
Size is not decided on aesthetics but on legibility. The reference we apply is simple: the height of the screen should be around a sixth to an eighth of the distance to the furthest spectator. If at a concert the last person is 60 metres from the stage, a screen 7 or 8 metres high guarantees they will see close-ups of the artist sharply. At a trade fair the calculation changes: the screen competes with dozens of other stimuli, so a raised position and contrast matter more than raw square metres.
- Trade-fair stand (audience 1-5 m away): fine pitch, surfaces of 2 to 6 m², content with plenty of detail.
- Presentation or marquee stage (audience 5-25 m away): P2.9-P3.9, screens of 4 to 15 m².
- Medium-sized concert or town square (audience 25-60 m away): P3.9-P4.8, main screen of 15 to 40 m² and possible side screens.
- Festival or large fairground (over 60 m): large-format IMAG side screens to bring the stage closer to the whole audience.
Brightness and protection: the difference between indoors and outdoors
An afternoon concert in summer or an open-air fair calls for outdoor panels with high brightness —in the region of 5,000 nits or more— so that the image is not washed out by direct sunlight. Outdoor modules also carry certified protection against water and dust according to the IP rating, usually IP65 at the front, which means they keep on running even if there is a downpour. Installing indoor panels outdoors "because they are cheaper" is one of the most expensive breakdowns there is: we have seen it and it never ends well.
Structure, power and safety: what you cannot see but holds everything up
A giant screen weighs hundreds of kilos and outdoors it acts like a sail in the wind. That is why a serious installation includes load calculations, properly sized towers or truss, ballast and a plan for wind gusts. The power supply also has to be planned: screen, video processor and sound system must be split across independent circuits to avoid drops in the middle of a performance. If you are closing off the rest of the technical side, you will be interested in our guide on how many watts of sound your event needs and our sound for events service, because image and audio are sized together.
“The perfect screen is not the biggest one, it is the one the last spectator reads effortlessly and the promoter pays for without a fright.”
Content that reads from a distance: less is more
A huge screen is useless if the content is not designed for it. For concerts, live vision mixing with close-ups of the stage is what the audience appreciates most; for trade fairs, short messages, large typefaces and high-contrast video loops work best. Avoid long texts, pure white backgrounds that dazzle at night and tiny logos. If your event is a congress or a convention in a room, the approach changes completely: we cover it in our guide to video walls for congresses. And if you want to see real large-format installations, take a look at our projects.