How many lumens does your exhibition wall need?
A single-sided backlit exhibition wall needs about 1,600 to 1,800 lumens per square metre of fabric, so roughly 12,000 to 13,500 lumens for a 300 by 250 cm wall. Above about 2,000 lumens per m² the image washes out, and even light matters more than the peak figure.
Hardly anyone asks this before ordering, yet it is the reason some lightboxes stop people on the show floor and others look grey.
What you are up against
An exhibition hall is usually lit to between 300 and 500 lux at floor level, and newer halls with a lot of daylight can be considerably brighter during the day. Your wall has to stand visibly above that, or it reads as a printed fabric instead of a lightbox.
A rule of thumb that works in practice: allow about 1,600 to 1,800 lumens per square metre of fabric for a single-sided wall. For a 300 by 250 cm wall, 7.5 m², that is roughly 12,000 to 13,500 lumens.
Why more is not always better
Above roughly 2,000 lumens per m² your image starts to shine through instead of glowing. Dark areas lose their depth and fine detail disappears. On a double-sided wall this matters even more, because the light has to pass through two fabrics.
More LEDs also mean more heat, more power and a heavier power supply. For a system you transport yourself, that is a real drawback.
Evenness matters more than the peak figure
A wall with 14,000 lumens spread unevenly looks worse than a wall with 12,000 lumens spread evenly. Visible hot spots along the edges or a dark band in the middle are what people actually notice.
So ask not only for the lumen figure but for the construction: how many LED strips per metre, how deep the profile is, and whether there is a diffusing layer in between. A profile less than 60 mm deep almost never spreads light evenly across a wall more than two metres wide.
Colour temperature
Ask for 6,500 K daylight, not warm white. Exhibition halls are lit cool, and a warm-white lightbox looks yellowed in that light. This is one of the few points you do not need to weigh up yourself: for a backlit exhibition wall, 6,500 K is almost always the right answer, whichever supplier you choose.
For our own walls, the colour temperature is not in the specifications yet. The figure comes from our manufacturer and has been requested; once it is confirmed, it will be on every product page instead of in this paragraph.