I'm currently trying to make 3D facemap of a black woman, who has very dark mahogany skin.
This involves uniting and blending three super-closeup, high-res photographs into one: a front view, and two side views.
Black skin presents a different set of difficult challenges. I'm finding that dark areas will suddenly have patches of very light shininess from the room lighting.
Getting areas to match is tricky, as there are not only dramatic tonal differences, but important color/hue/sat differences as well: a normal black face will have regions that veer towards a red-brown... and then other regions that veer towards a green-brown, so the usual techniques of Cloning just don't work well. Virtually ANY retouch you do of black skin is going to be noticeable because of dramatic tonal differences throughout...
Has anyone written a book or made tutorials about retouching black skin?