You have to adjust it in the settings tab before you start the game. I set the HDR to High and adjusted the gamma correction to 80. That gave me what I like for my system. However I would imagine all that varies depending on what drivers your using and what video card and monitor you have and of course what setting you have your drivers set to. Its all a lot of tweaking to get the right look. Your best bet is to play with it only using the gamma correction in the games setting tab. You don't want to change things and have it look bad for all other games while ROF looks great.
Rob
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