Here's an example of fake color in a 1951 publicity still, from the Nov 1983 issue of Starlog
magazine. Apart from accuracy issues, it's pretty good. But it doesn't reveal anything about true colors in the production:
The reversed colors on Superman's outfit remind me of a GREATEST AMERICAN HERO episode. In "Dreams" a gangster previously bagged by Hinkley and Maxwell has double-talked a parole board into letting him out. While trying to turn the tables on our heroes, the gangster sees Ralph in action again. The problem is, neither of his henchmen see Ralph doing his superguy routine, and neither was present to see it when the gangster was caught the first time—
Johnny: There he goes. This guy can fly. He can fly, I don't believe it!
Thug 1: We lost him. There was a holdup across the street. He slipped out the back.
Johnny: Did you see him fly past here? He came around the side of the bank about ten feet off the ground. Flies after them—you seen that, right?
Thug 1: Fly? I, uh...
Thug 1: Well, Johnny, I was kind of ducking for cover in the bank, there. (To Thug 2) You must have seen him!
Johnny: I ain't nuts here! I seen him fly past here! And I wanna hear you see it, too! I wanna hear it!
Thug 2: I kind of saw this blue streak going by, or something like that, I guess.
streak! The super guy wears red!