Susie from Propstar had a camera and I have pictures of my tech (Drew) and I in the senator's office, in front of the United States seal and other such memorable pix. During our positioning of the phones, lights and cords there was some guy sitting in the senator's chair. I thought to myself, he looks a lot like Tom Cruise. Well, he's Cruise's stand in. While they are setting up camera shots, lighting, rehearsing moving camera shots, etc. they use stand ins to do the scene. The stand in for Meryl Streep and Cruise were very similar in body type, basically they are supposed to be doubles, so same hair/eye color, same skin tone, same height, same body type, wear the same clothes, etc. This is for lighting, camera angle, prop placement, etc. Because we sure wouldn't want Meryl Streep standing around while they got the lights right, eh. She was lounging about in her Star trailer while all this was going on.
By the way, I forgot to tell you that I saw all 3 of the stars, Meryl Streep, Robert Redford and Tom Cruise. I only saw Cruise for a couple seconds. He's quite a short little fellow. Meryl Streep is beautful and she laughed a ton on the set during rehearsals. Robert Redford sat about 3 feet from me while he was discussing scene changes with the script guy. Him and Cruise apparently co-direct and co-star in the movie. While we were on set Cruise was acting, so we didn't really see him behind the camera. BTW, directors aren't really behind the camera, the camera guy is. The director just reviews the clip, makes corrections as he sees fit, etc. The one long (if you could call 30 seconds long) scene that I was there for too 3 hours of rehersals and about 14 takes. Some of the takes were ad libs by Meryl Streep (it was her scene), some were exactly on script and some were just flubs. Not flubs on Meryl's part of course, she was always perfect, except of course when she dropped her lipstick across the floor. hehe