Galaxy Quest (1999)

The joke starts with the frame. The movie opens on the cancelled TV show its washed-up cast is still famous for, then the picture grows in two steps: to a standard 1.85:1 for roughly the first twenty minutes, and finally to full 2.35:1 widescreen once the adventure turns real. It's a sly way of saying these actors have just walked out of television and into a movie, and it costs the comedy nothing. You can enjoy the Star Trek send-up without noticing the change at all, and grin when you do.