Hi! ambient occlusion is a way to increase the shadows… is it impossible to get ambient occlusion AND indirect lighting, in the same render?
A kind of ambient occlusion is supposed to be included in full indirect lighting (recessed area do not get much light from indirect lighting). It’s subtle and one may want to stress that effect.
Anyway, it can be improved in post. You render once with ambient light on and AO and use multi pass to save the AO map.
You render then with indirect lighting and compose in post (use multiply operator on the AO map) using photoshop, gimp or whatever software able to blend layers.
I’m working on a plugin (a post renderer) that add AO to a render, but it’s far from being ready.