Brightness Completely Maxed Out

Brightness Settings so bright that I can’t see. Restarting, lowering GPU gamma doesn’t work. Any ideas? No options in game to adjust brightness.

That ability was taken out a few patches ago due to some sort of problem with it.
I personally don’t have that problem on my PC.

Drink a NightHawck potion and just wait 'till effects fade away.

I don’t know if you are experiencing a rare bug fixed in 1.7.1 patch, could you check your game version?

1.7.1 patch note:

  • Absurdly bright screen caused by persisting effect of Nighthawk potion during daylight has been fixed. Any remaining issues can be solved by drinking another Nighthawk potion and waiting for a few hours.