I just need to pipe in about something that has bothered me for years on this forum. I want to let everyone know that I'm not pointing any single member out as I've heard this from many people and think that the theory has just become fact over time. The idea that ILM painted models very heavily to compensate for the extreme studio lighting used in filming is a complete farce and misconception. It doesn't matter how bright the lighting is as long as the exposure of the camera is set correctly it will look just fine. In fact, I will argue that bright light will allow you to see details of painting better. So saying that they were "blowing out" these models with lights is then insinuating that they are not able to expose there subject matter correctly. I will further argue that the opposite is true, that the ILM models were painted heavy for the detail to show up under low lighting conditions. Case and point if you look at the film during space battles, the ships are under exposed on purpose because, hell they're in space and it's dark. It would look absolutely fake to have the dark of space and a beautifully exposed ship flying through the screen. That's why on any screen grabs you may notice you can't see most of the colors or details on the ship. Another sure indication of low light is film grain. High ISO's always constitute more graininess, even if shot digitally.
I don't ever claim to be the most knowledgable about Star Wars lore, or claim to know everything about modeling, but one thing I will defend until I die is that I know photography and lighting as I've spent over 15 years as a professional photographer. So there is my rant about the heavy paint because of bright studio light theory.