I am on a stock Ubuntu 20.04 LTS machine with gnome. Using the brightness controls on my keyboard ('fn' + left/right arrow keys), I can adjust the screen brightness up or down (this brings up a gnome-styled slider and sun-like brightness icon, showing where I am in the range between lowest and highest brightness).
Going by the values in
/sys/class/backlight/intel_backlight/brightness, the brightness varies between
120000, in increments of
I can set the brightness to other values by redirecting to the
/sys/class/backlight/intel_backlight/brightness file (*). To my surprise, the modification persists even through keypresses to change the brightness (i.e. setting it to
3600 and then pressing 'fn' + right arrow once yields a brightness of
9540 (= 3600 + 5940) (**).
However, what I really want is more fine-grained control. I'd ideally like to change the existing
5940 to something more like
I did try
grep -r 5940 /sys/class/backlight/intel_backlight/* in the hope that the value might simply have been stored as a writeable setting somewhere, but no such luck. Apart from that, I'm at a loss as to where to look. I could swear that the values (both the minimum and the increment) were different back in 18.04 (on the same physical machine).
(*) For some reason,
drubbels@drubbels:~$ sudo echo 3600 > /sys/class/backlight/intel_backlight/brightness
drubbels@drubbels:~$ su Password: root@drubbels:/home/drubbels# echo 3600 > /sys/class/backlight/intel_backlight/brightness
(**) It does get 'squashed down' back to the existing minimum or maximum of
120000 when I try to take it below or above those.
Note: I do not believe this is a duplicate question. I did find a number of other similar questions complete with answers, but most of these were from 2012 and referenced settings & menus which no longer seem to exist