Just a neat little post I was thinking about...
AO (Ambient Occlusion) adds a darkness to your character, in a way, your character already has AO.
But with AO layer, you can strengthen or weaken it.
This is my character with AO disabled. Meaning, she essentially does not have a AO Layer on her. (All done without camera Light)
If you didnt notice, under her chin/jaws it gets very dark. Same goes for her Mouth, it goes dark in there.
In some way, you would say this is desirable. For me it isn't but youl see why...
This is AO set to 0 (on the upper right AO slider)
Suddenly, you notice that she appears to be very dark, while her fluff stays the same. This is why I find AO on 0 to be undesirable. Is this an issue? (Honestly, I dont know. I would assume so but again, im good at working around stuff) Probably not for me, since I like to do what comes next.
Here I set the AO to 1 (Which means... no AO, and relatively there are no significant changes being made to the character in terms of where she is in lighting conditions. The real difference is that shes not too dark within dark areas.
AO on, set to 1
AO on, set to 0
AO is OFF
Admitedly, I do like the dark areas, but the interference with the fluff breaks the consistency a lot. So I personally keep it at AO on, set to 1.
Hard shadows are made anyway with AO on, set to 1
Compare it to No AO
Its darker, but not that much more believably dark. With no AO the fluff is more visibly inconsistent.
I guess these are the drawbacks to working with fluff.
The place I advise to make another AO layer and set it to 0 is at the inside of the mouth.
AO ON, set to 1
AO ON, set to 0
My little tip for you then if you will follow my advice is to have 2 AO layers, one for everything, and one for the inside of the mouth.