4k Monitor brightness control?

[yushi90]

Hi everyone,

is there a known way to control the brightness of a DP attached Monitor by system? I found a somewhat buggy shell script to set the brightness with DDC-CI, but that does only accept levels like 50%. The increment or decrement option does not really work.

I hope, someone can help me with this.

 

[slim.jim]

The only "solutions" I have seen mimic brightness control by overlaying the whole screen with a semi transparent black layer.

 

[schwingel]

i'm using an app called brightness slider. not ideal but helps

 

[Pieroman69]

DDC is the proper way to do this, as the apps that overlay a black transparent window decrease contrast and color range. Unfortunately DDC suffers from bad support from everyone (monitor constructors and apple SDK), which is why DDC-CI can only set a brightness and not retrieve one (which is why you can't do the relative adjustments). However by looking how it's done in https://github.com/kfix/ddcctl/commits/master you should be able to do fine adjustments.

Another way to play with the brightness is something like https://justgetflux.com, which I think acts on the video card LUT, which is a better solution than the transparent window.