I never took into consideration the actual tungsten studio lights or the film. I had honestly always assumed that the different looks were due to the many shades of colored lighting throughout the different sets.
I’ve always been fascinated with trying to nail down the actual colors of certain things on the show: The Bridge railings and trim, the Saurian Brandy bottles, the recently discussed salt and pepper scalpels, Kirk’s tunics. There are so many factors–including time’s inevitable wear/bleaching/fading–that play a part in figuring out what they actually were. I guess “Command Gold” has been incorrect for a very long time.