Revealing mistake: When Strahm's phone says "no signal" there is actually a three bar signal. (00:06:35)
Revealing mistake: When they are sitting down for dinner at the old lady's home, it is clear that a very white light source is in the room brightening things up - something that non-electric oil/kerosene light sources cannot do.
Revealing mistake: When the Porsche Cayenne is lifted out of the water at the scrap yard then placed on the ground, if you look through the gap between the front passenger wheel you can see the engine is removed from it.
Revealing mistake: Lighting screens are constantly reflected in McQuarry's glasses all through the film.
Revealing mistake: After Mahogany is thrown off the train, as the train brakes and begins to stop, there is a shot of one of Mahogany's hung victims and you can see the whole body vibrate like rubber, which it was made out of. (01:21:47)
Revealing mistake: As Rob, Hud, and Lily are rescuing Beth from her apartment, the view outside the window is tilted roughly 45°. This is due to Beth's apartment building being partially collapsed against another building, demonstrated previously by an exterior shot. However, the characters are moving within the apartment with no difficulty or apparent change in gravity, even though they should be struggling to remain upright in a significantly tilted apartment. This makes it clear that the scene outside has been added using chroma key technology, and the camera has simply been tilted to create the illusion that they are on an angle. (01:01:30 - 01:01:52)