I used this recent zbrush sculpt to test out my different rendering options. Which essentially equates to me meddling around for far too long and figuring out how to get the lighting to do what I want. Sculpting is one thing but actually getting the small details to show up is another. The bust itself started out as a dynameshed sphere.
Renders in Zbrush, which are quicker to generate but not as realistic in terms of how light actually works. The images themselves are generated as psd's whereas I can get tiffs out of keyshot.
The rest are renders from keyshot.
Straight keyshot renders. The image on the left provides the lighting direction and deep shadows, the one on the right is used to fill in any surface detail lost in said shadows.
Taking the vanilla renders into photoshop. I darkened the second image and brought out more detail by overlaying it on top of itself as multiply and overlay layers until it matched the first image in terms of value. Then both images are placed overtop each-other and I mask out the features I want to discard. That along with high-passes, level adjustments and the usual tweaking produce the image below. Still not entirely what I was after but I think I'm getting close.