When Geralt is near a wall, it creates an aura of darkness around him and looks very unnatural. For example:

http://i.imgur.com/7r6a5.jpg

The dark area surrounding Geralt also moves around depending on your camera angle, as if the camera is actually a light source.

It doesn't only occur near walls.

The SSAO in TW2 just feels really pronounced. It can make some scenes look more realistic but at the same time can make others look less natural. I'm not sure if I should have it on or off. >_>

If thats the case, then the shadow would be behind Geralt isn't it..unless you take the minute amount of light rays bending on the edges of leather armor's fabric!. :) It appears as if Witcher 2 is utilizing view_space buffer is used for SSAO, instead of depth_space buffer.

or

Its related to the number of blur passes for the spatial accuracy, which I think increasing the value puts EXTREME load.

Yeah, it looks really weird, especially in the kingslaying scene. It made characters feel very disconnected from the rest of the scene, in a very unnatural and distracting way.

I have no idea what any of that means >_>. So can something like this be tweaked? I haven't experienced the 'problem' I'm describing in other games I've played that use ambient occlusion, though I've read that this "dark aura" is normal with SSAO (yet I didn't notice it when playing Crysis, though that was long ago).

The unnatural-looking dark aura surrounding Geralt plus the decrease in performance made me turn off SSAO.

The terms won't mean much other than the fancy looking names, unless you know anything related to 3D space rendering (for this game; it is specifically related to lighting steps of deferred engine rendering)...nvm.. bla bla bla

the Halo is also visible in Crysis when you look at the gun, its very easily noticeable when you move the screen against backgrounds of different contrasts. The effect is like air hitting the weapon and an elongated strip/band of black dissipating wingtip vortice like effect is seen around the weapon from the camera's view point. (tweak-able off course, there are nine r_SSAO_<values> easily available via console in the game).

I wish there was a config file/SSAO alteration settings in the ini files for Witcher 2, which could be tweaked. :)