I'm sure you've seen one of the snippet Darth Editous put up way back when for the Cloud City duel matte painting. The one with the establishing shot of the control room hanging over the pit (sorry, I don't know what this is called). Anyway, in the movie as is a matte painting was used with some added blinking lights. As the camera zooms in, there is no obvious perspective to the shot. It looks like someone's just zooming in on a painting. DE reworked it a bit and gave some perspective to the existing painting. I'll try to find that link in DE's thread...

edit: Ah, yes. It's the weather vane. That's what it's called. Oh well, the link is dead anyway and Ady commented on it so is aware of it's existence, so there you go.