Similar here - my cube is as dark as I can get it (which really just means the lights directly overhead are off), and my monitors are at the minimum brightness setting. My screens glow, guys. I don't need to light them up externally.
Any reference on working with lights on vs off? I've seen 1 or 2 people do that in office. I've been told that lack of ambient light might cause more strain. Is there any study supporting what you've said?
Only my own anecdotal study here. It's not total darkness, because I'm in a well-windowed cube farm (along a far wall that has no windows, though), so there's still a bit of ambient light.