How to calibrate display in Ubuntu 20.10

DisplayCAL no longer works as the python 2 library has been deprecated and is not updated.

There is a solution using ArgyllCMS.

Steps:

Open console
install ArgyllCMS. sudo apt-get install ArgyllCMS
run dispcal to find out the monitor you need to calibrate
run dispcal -d X -v -o profile-filename (where X is the monitor number )
In this order:
- 2 adjust the color (I put my monitor in sRGB mode)
- 4 adjust the brightness
- 5 check all
- 7 calibrate

Takes half an hour, produces a color profile icc file that you can load into your monitor’s color settings.