The number on the brochure is a maximum
A 6500-nit cabinet can run at 6500 nits. It does not have to. Most outdoor screens spend their life at 60 to 75 percent of rated brightness because the content does not need more and the power bill does not want more. Rated brightness is headroom, not a working point.
Match it to the sun, not to the competition
| Situation | Usable brightness | Notes |
|---|---|---|
| Covered walkway, north facing | 2500 – 3500 | Reflected light only |
| Street level, direct sun part of day | 5000 – 5500 | Most common outdoor spec |
| Open plaza, sun on the face all afternoon | 6000 – 7000 | Needs auto-brightness sensor |
| Highway billboard, viewed at 80 m | 7000 – 10000 | Text height matters more than nits |
What high brightness costs you
Doubling brightness roughly quadruples the LED drive current in the same module, and that shows up as heat. A 6500-nit wall in Riyadh in August will run its fans at full speed by 11 a.m. and the power supply will age faster. If you do not need the headroom, buying it shortens the life of the screen.
The setting everyone gets wrong
Auto-brightness is often left at factory default, which is usually a fixed 100 percent. Enable the sensor, set a night floor around 800 to 1200 nits, and set a daytime ceiling you actually measured on site. On a screen facing west, the correct ceiling changes by 40 percent between morning and late afternoon. A fixed setting is wrong for half the day.
One more thing about grey scale
At 6500 nits, low-grey detail gets compressed. Faces in shadow turn into flat patches. If your content has a lot of dark video, a 5500-nit screen with better low-brightness linearity can look superior. Ask for a grey-scale ramp test at the brightness you will actually use, not at maximum.