Calibration

sudo apt-get install xcalib
sudo apt-get install icc-profiles
xcalib -c
xcalib -brightness 0.0 -contrast 60.0 -gammacor 1.3 -alter
xcalib -brightness 0.0 -contrast 90.0 -gammacor 1.5 -alter
xcalib -brightness 0.0 -contrast 100.0 -gammacor 1.5 -alter