"One of the ways to understand how light works in photographs is to do basic exercises. We did one way by creating the portrait lighting cheat sheet that shows how positioning a single light effect a portrait, others have done similar stuff with an egg.
Photographer Pat David had another idea. Using a CC-BY 3D scan by Infinite Realities and an open source 3D modeling software called Blender 3D (Blender is darn near real rendering engine, it can even mimic shaped bokeh), he started to play with positioning various light sourced around the scanned head."
Via Philippe Gassmann