I have Ubuntu Mate 16.04 installed on a sub $400 laptop that has a very dull and washed out display. To make the display look better I adjusted the gamma with the xgamma command.
To see what xgamma can do, open a terminal and run
Which will return:
usage: xgamma [-options] where the available options are: -display host:dpy or -d -quiet or -q -screen or -s -version or -v -gamma f.f Gamma Value -rgamma f.f Red Gamma Value -ggamma f.f Green Gamma Value -bgamma f.f Blue Gamma Value If no gamma is specified, returns the current setting
As you can see from the availible options, -rgamma adjust the red gamma, -ggamma adjust the green gamma, -bgamma adjust the blue gamma, and -gamma adjust all three at once. The f.f is to be replace with a numeric value.
To improve the look of the display, I ran
xgamma -gamma 1.00 in the terminal and continued to change the numeric value until it acheived the desired results. I'm currently using
xgamma -gamma 0.80
From there I added this command to Startup Application Preferences.
So now every time I login, the gamma is adjusted and the display looks much better.