The dewback, from which the trooper steps down, has some strange colors on it's head. But than also the R2 unit, that passes the scene when Kenobi and Luke are stoped by the troopers, has a green stripe not red as everyone says. So what could be causing these two problems? The rest looks OK color-wise.

BTW, I like Vader's black eyes. My way of looking at this is, in SW3 when they put his mask on, the inside of the eyes looks red, and that is what his vision is going to be, but from the outside it is pure glossy black! It is intentionaly semi-transparent. You cannot see inside but he can see you.