Revealing mistake: On the ice the tank is firing - in slow motion we see empty shells are littering the area. The shells have crimped ends, revealing them to be blanks.
Revealing mistake: During the opening trap, at one point one of the five "Bucket Heads" starts banging on the wall behind them. If you look very closely, you can see the set-wall waver slightly as it's struck, revealing it's not really a concrete wall. (And it's not supposed to be the doorway that is later revealed during the final twist. It's a separate section of wall). (00:05:40)
Revealing mistake: When the FBI agent is in the room of the court medic to get the cause of death, in several shots the sliced up corpse is breathing. (00:27:00 - 00:29:30)
Revealing mistake: In the beginning of the movie, when John get his Mustang, he starts accelerating deliberately to hit one of the cars (black sedan), but right after the odometer scene (where you see the gas going up) you actually see the car is stopped. It is pretty obvious. (00:09:30)
Revealing mistake: Back at his NAACP homebase, Marshall meets with the boss who is already sending him to deal with another case. In the close-up of the newspaper he's reading, check out between the actor's fingers. You can tell that half of the article, which begins in English, suddenly switches into Latin 'lorem ipsum' filler text. (00:06:20)
Revealing mistake: To kill the second and third guy at the food court, Eddie does a rather unlikely slide across the floor. His shirt is pristine even in the back, despite having sailed across soda. (00:57:40)
Revealing mistake: Addison is driving straight, but cars behind him are shown going around a curve. (Use of a green screen). (00:55:50)
Revealing mistake: When Jon and Ponch are giving chase to the bikers after spotting them from the overpass, they are cutting through by going down the slope, dangerous and steep. Despite being such a daring move, there are already multiple tire tracks on their path. (00:40:25)
Revealing mistake: When the police are going through the closed circuit video where the little girl sees Freeman's face, one cop says to freeze the video. It stops a fraction of a second before he says anything.
Revealing mistake: As the train approaches and stands in Brod Station, it becomes rather obvious that the smoke emitted by the steam locomotive is "painted in" by computer. It does not move or change shape as real smoke would. A shame, as the steam effects earlier in the film are very realistic.
Suggested correction: No it's not the section that is a door, but that door does prove vital here. By showing the door, shows there is a section behind the wall. Meaning the wall we see is most likely a completely false wall and not the structural wall. With it being a false wall it is entire pleasurable that it could move.
Ssiscool ★
When Jigsaw opens the door, you can see the walls are indeed solid and are at least 6-8 inches thick. Given the fact they appear to be made of concrete and run floor-to-ceiling, sorry... there's no way they are moving when someone bangs on them. Also, why would Jigsaw make a "false wall" that was so easy to move when someone hit it? He'd be setting himself up to possibly be caught. Sorry, but this particular correction is just too far-fetched. It's just a mistake.