With two screens (dual head using Xinerama feature of Xorg), the Gamma correction feature under 'Display Preferences' suck completely and make the second screen takes the background of the first screen and stop working.
Humm, there is no correlation between the gamma correction and the background picture. Are you sure this is not a bug in xorg? Did you try with some other similar tool?
Can you try with xgamma? If the problem arises with xgamma, then it's an xorg bug. xgamma -gamma .8
(In reply to comment #0) > With two screens (dual head using Xinerama feature of Xorg), the Gamma > correction feature under 'Display Preferences' suck completely and make the > second screen takes the background of the first screen and stop working. > I've tried with the xgamma tool in the terminal and it's working. Here the command I use to test it on the terminal -> xgamma -display 0:0 -gamma 0.75 One note: Into the terminal, it's worked for one screen and not for both screens like it does if you use the GUI to set it.
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