Quite literally, I did nothing but turn off the sepia tinting. All other post effects including HDR/bloom are still active and at exactly the same level they were before. It's actually the sepia tinting to everything that gives the game that 'intensive' look, making everything glow yellowish.
If you use the file I provided and step into a dark area and watch the lighting, then step out into the light and watch closely, you'll see the HDR is still active it's just more subtle than people might expect since so many improperly blamed the HDR and deferred lighting for that orangish glow when neither in fact had anything to do with it.
I may in the future fiddle with the numbers themselves and see if I can't find a happy medium, keeping some of the haze effect that the sepia overlay added without overly affecting the colours of everything else, but frankly that work is better left to a graphics artist than myself. I can read code, but I don't know from pretty. It's really just a matter of altering RGB numbers, but I'm used to RGB editing having simply three numbers to alter hue. This one has xyz coordinates for each colour, and I can't quite seem to get my head around how that works yet. I can only imagine at this point that those are in fact XYZ coordinates for the source of the sepia tinting for each of the three colours and that the tinting itself (sepia_r, sepia_g, sepia_b) is actually a procedure call to somewhere else - meaning simply changing the numbers in the post_effects.xml file may just alter the source location of the tinting rather than altering the LEVEL of the tinting.
I'm such a graphics noob that I'm not even sure if I'm explaining that correctly, but -I- know what I mean, even if no one else does.
Hey, can you make a new link to that xml? I'd love to turn off post effects, it kills my frames, yet I'd love to still have Night Vision.