Originally posted by anthony mazzeri And thanks again, LeRolls!
Tabbakh, I'll do you one better and draw you a diagram.
The single light source was natural sunlight through a window in an otherwise dark room just to camera left. You could replicate this setup with a strong flash side/backlight with some softer frontal diffuse fill light. The key I think was raising him level with the window so the light is coming from directly behind and to the left instead of from above if he was down on the floor. And then extremely heavy vignetting in post (Aperture) to exaggerate the chiascuro effect.
Thanks for your helpfulness with the diagram and description. I've gotta try this out...