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.
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.
Trivia: In keeping with the theme of no books this movie has no text visible anywhere except the opening theatrical logo. Even the credits are not shown on the screen. The only symbols shown in the movie are numbers, such as the 451 medallions on the fire crews and their equipment. Signs can occasionally be seen in the background.
Clarisse: Is it true that a long time ago, firemen used to put out fires and not burn books?
Guy Montag: Your uncle is right, you are light in the head, put out fires? Houses have always been fireproof.
Clarisse: Ours isn't.
Guy Montag: Well, it should be condemned, destroyed, and you'll have to move to one that is.