I own an Acer Aspire E5-773G notebook running Ubuntu 16.04 with Unity Desktop.
When I change the volume or screen brightness level (no matter whether using Fn+Arrows or through e.g. the Volume Indicator), the scaling does not seem natural.
There is nearly no notable difference between the steps in the upper third of the brightness scale and in the upper fourth of the volume scale.
On the other hand, the steps between slider positions in the lower third of the brightness scale and in the lower fourth of the volume scale seem huge. Especially the lowest brightness setting is extremely darker than the second lowest setting (but not off).
To me these scales seem technically linear, but as the human senses all operate logarithmically, they seem weird. Is there any method how I can change the scaling of mainly brightness and ideally also volume to a more logarithmic one so that the steps seem more equal?
xbacklight tool does not work on my machine for whatever reason. However, I found two alternatives:
Dbus: You can use the two commands below to get/set the brightness value as percentage, i.e. integer number in the range 0-100:
qdbus org.gnome.SettingsDaemon.Power /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.GetPercentage qdbus org.gnome.SettingsDaemon.Power /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.SetPercentage 42
The advantage of this is that every user can run it without special privileges. It is less fine-grained though.
Direct access to
/sys/...: You can use these commands to get/set the brightness level as raw integer number in the range of 0-x. The actual maximum value x can be found using the third command:
cat /sys/class/backlight/intel_backlight/brightness echo 42 | sudo tee /sys/class/backlight/intel_backlight/brightness cat /sys/class/backlight/intel_backlight/max_brightness
The advantage of this is that it provides direct access to the hardware capabilities, so this is the most fine-grained control we can get. Unfortunately, changing the brightness value requires root rights (note the
sudoin the set-command).