Revealing mistake: Right in the beginning of the movie, we see young Viktor holding a gun to a young girl, about to shoot her. The gun is a revolver and as it comes into focus, you can see there are no bullets in the gun. This is part of a later scene in the movie where Viktor kills his first two people. As he's shooting, you can again see there are no bullets in the gun. (00:01:20 - 00:23:10)
Revealing mistake: In some of the shots where Greg is in the pool with no swimsuit on, you can see that he is wearing shorts in it before he asks the girl to give his swimsuit.
Revealing mistake: After The Corpse first gets back out of 'hell', he saves a girl from some zombies in sleeping bag-like sacks. As they jump towards him, the animation is bad and they flicker around on the ground like a game glitch. (00:11:30)
Revealing mistake: When Alice shoots the zombie in the blue dress, we get a frontal shot of the gun. Pay close attention to her trigger finger: it doesn't move at all, while the gun does fire.
Revealing mistake: When Dredd throws Kay onto the table, Kay is supposedly handcuffed, but his hands spread apart way further than they should have.
Revealing mistake: When Picasso removes the first finger from Fan Yau Lee's hand, you can see that there is no blood on the instrument used.
Revealing mistake: When Curtis or Catherine are driving while it is snowing (e.g, on their way to the Christmas party), there is relatively heavy snow going horizontally past the side windows but there is no indication that "snow" is falling on the windshield. Wipers can't be heard (like one would expect driving in these conditions) and there is no dimming of light inside to suggest the heavy snow is blocking some light. Also, the way the snow is accumulating around the side windows is not typical. (00:33:04)
Revealing mistake: When the cops raid Hoyt's apartment building, Billy the dog is barking at them. But when multiple cops reach his level, Billy whimpers and takes off up the stairs scared. However, you can see the dog's tail is still up and partly wagging. A scared dog's tail would be tucked between its legs, even when climbing stairs. (00:50:35)
Revealing mistake: When Wyatt is in Katie's house we can hear him call his sister's name, however he says Kathryn, which is the actress that plays Alex's real name.
Revealing mistake: When there is a flashback of Thorin in the war, in the first few seconds, on the left of the screen, there is a man with a shield. He swings it at an ogre and you can see it misses by a good five inches, but the ogre moves his head back as if it were hit.
Revealing mistake: During the shooting in Candieland, right before Django bursts a man's head, a man next to Django who he uses as a shield has his chest burst. The blood pack is very noticeable.
Revealing mistake: When the three characters are playing with legos and Matt is told to start playing music from his ipod, you can see that the sound is off and the ipod is paused when the music is apparently playing.
Revealing mistake: Considerable efforts were made for this film to have Joseph Gordon-Levitt resemble Bruce Willis (colored contacts, nose prosthetics) since they are playing the same character at different ages. Yet the two actors' ears remain distinctly different. Bruce Willis's ears are much larger than Joseph Gordon-Levitt's, and Joseph Gordon-Levitt has connected ear lobes while Bruce Willis does not.
Revealing mistake: IChat is used to make a second call to Professor Jonas, only this time we can see Professor Jonas is online under "Bonjour". Without too much detail this would mean that Professor Jonas is in the same house (on the same LAN) as Ellison. (01:31:55)
Revealing mistake: When The Deputy Charley Rakes goes to Cricket's house and attacks Jack, you see Charley throw Jack down the steps outside the house. If you look closely, you can see he lands on something really soft and spongy like a mattress which is hidden under the foliage on the ground to break his fall. When Charley walks down the steps towards Jack, you see him walk on it, which again looks really soft and spongy.
Revealing mistake: When Cam punches the dog, you can tell that the footage was sped up.
Revealing mistake: In the scene after Will leaves the girl at the train station, the scene cuts to a downtown district. Many of the extras used for that scene are seen watching the scene being filmed. (00:57:00)
Revealing mistake: In the lead up to the final scene, prior to the cranes being in alignment, when Spider-Man is jumping between buildings, he falls down to a fire escape, and you can see that the bars or rails on the railing he lands next to are not made out of metal as they easily move as the actor or stuntperson moves next to them. (01:48:42)
Revealing mistake: When Luke is signing the receipt for his new clothes, the amount on the CC receipt is less than $10.00. (00:40:16)
Revealing mistake: When Niles York first appears on camera beside the plane bearing his name, most won't notice, but you can see the pilot's hatch open, revealing that it is not a passenger jet, but a fighter plane. You can also see the air intakes on the wing, further evidence that this is not a passenger or private jet. (00:02:11 - 00:22:18)