Thank you. Will look into this.

Depends on the environment. On my MBAir, if I’m in the living room, then it’s usually at 8 or 9 out of 16, if the lights or on or it’s day and I have the blinds open. Once in a while I can’t sleep, come downstairs in the middle of the night, and do something on the MBAir. with the lights off, screen at 1 out of 16, and keyboard backlight on (it’s usually off). If I’m on the back porch during the day, though, it’s gotta be 16/16.

Keep in mind that not all monitors have the same brightness - even the same model. I’ve had three LG5Ks (as I wanted to check the backlight for evenness) and one of them was noticeably brighter than the other two (the one I kept! )

For me I am usually between 50% and 75% or up to 100% for some video sources or if it’s very bright outdoors… but it should depend on the brightness of your room and what’s comfortable for you.

If you’re finding things uncomfortable, or too contrasty, it could be a sign of underlying health issues (or even something like borderline diabetes):