Gamma control - can't adjust.

[Jusko]

Hi.

I have problem with Penumbra Collection. At first start there is gamma control to adjust brightness. The thing is, that it's not working. I can turn gamma to 0.1, but nothing happened - game is bright as it was (there is almost no need to turn on glowstick or flashlight, because i see near everything without it). Sure - I can adjust monitor gamma, but even when monitor gamma is set on almost maximum darkness, game still is too bright for me. Why I can't adjust gamma from game (maybe this settings are too deep in X to change by game)?

Distro: Fedora 17/18 x86_64.