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I want to set my brightness lower than the 1-tick brightness accessible via the brightness buttons.
I have seen utilities like Shades but that won't work, it uses an overlay over the screen and this leads to fake-looking blacks and ugly colors, and the backlight is still too bright.
However I've noticed when I turn brightness from 1 to 0 the screen fades out.
This means clearly it's possible for the screen to display a brightness lower than 1.
Also quickly switching between 1 and 0 makes the screen consistently stay at a lower brightness.
How can I make my screen permanently a lower brightness than the current "lowest"?
Also I forgot to mention I have tried Alt+Shift+Brightness, to move in quarter increments. It doesn't change the brightness (at least noticeably) once it is less than 1 "big" tick.
I have a Macbook Pro with Retina Display 15" from Mid-2015.