RoccondilRinon said:
He definitely had extensive makeup in ROTJ. Personally I'm of the opinion that they didn't need to show a moment when he changed from human to deformed, and that a gradual decay worked better; if you look at his makeup in AOTC you can see he's starting to change already and I think that was originally the way they were going to go, but in ROTS he's back to normalface until he zaps himself.

yea, but then you would have the people who would complain, "How did he turn white?"