With light backgrounds and dark text it is much more important to get the screen brightness right, as a 100% bright display in a dark room just messes up your night vision and as it's night ...

Despite the fact that we accurately perceive the screen to be very bright in relationship to the rest of the scene our eyes take in, our eyes attempt to adjust based on the average brightness ...

As bright, perhaps, as if you were standing in that wood yourself. It would be more realistic, since the thing on screen that's supposed to be bright is actually physically bright.

That might mean staring at a computer screen that is very bright could damage your eyes.” He says there’s also some experimental evidence indicating regular exposure to computer-strength light ...