Enterprise Bridge Showing Set Elements
In this picture the crew on the bridge are visible. But also - you can see three stage lights above and a cut away in the floor below on the lower left of the scan. The camera and dolly was rolled in through the cutaway for filming the actors on the bridge set, and dozens of various kinds of stage lights were hung above and used to illuminate the various working stations and actor positions. This shows the set that was shown and filmed regularly during Star Trek TOS production.