CyanogenMod/android_device_samsung_crespo — comment on commit 093f6e1b13c9bb7cbf9139b477946f2132e451c1
File:  line 0
By KalimochoAz:

wait until next nightbuild.

good values are -14 -17 -20 for gamma.

There was some issues there so if you have used the NB then add this new values. On a new instalation the values remains.