I like my monitor dim and red-tinted at night. I used to use
xcalib -green .1 0 1 -alter xcalib -blue .1 0 1 -alter
on my laptop. I'm now using a raspberry pi2 with an HP 2010i monitor and
xcalib is completely ignored. Likewise
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xgamma work on your pi with another monitor? Likewise, if you have another Linux box, do both utilities work for your monitor?
Another idea: have you tried using redshift? From the website:
Redshift adjusts the color temperature of your screen according to your surroundings. This may help your eyes hurt less if you are working in front of the screen at night. This program is inspired by f.lux (please see this post for the reason why I started this project).
Also f.lux can be your answer.