Visible crew/equipment: Near the end when Montag arrives at the Book Peoples' commune, he is greeted and ushered into a house. There's a shot from just inside the building, looking out a window towards Montag and his host as they approach. As the POV shifts a little, a reflection of the camera becomes plainly visible in the window glass.
Fahrenheit 451 (1966)
1 visible crew/equipment mistake
Directed by: François Truffaut
Starring: Julie Christie, Cyril Cusack, Anton Diffring, Oskar Werner
Revealing mistake: Near the beginning, Montag puts on the fireproof clothing to use the flamethrower. It's really footage of him later taking off the same equipment played in reverse.
Guy Montag: Tell me, this uncle of yours, did he ever tell you not to talk to strangers?
Clarisse: No, he did say once if anyone asked how old I was to say I was 20 and light in the head. They always seem to go together.
Guy Montag: Light in the head?
Clarisse: Mm-hmm, loopy, crazy.