So there's lot's of on-set pictures from the OT, but there seems to be a lack of those featuring the two main villains; Vader and the Emperor. First of all, the Emperor was an interesting character that was realized for the movie, featuring prosthetics and superimposed chimpanzee eyes on actress Elaine Baker. Suprisingly, I've seen no photos of the character being brought to life. Second is Darth Vader, but specifically, him during the unmasking scene, portrayed by David Prowse. We only see the back of his head onscreen, but no other photos exist. I'm really curious about where the makeup was at that point, even if only the back was finished at that point.