Revealing mistake: In several scenes Superman has fillings in his teeth.
Revealing mistake: When they are at the Nutmar camp in the mountains, Val Kilmer tells Willow "Get on that shield!" but when they go over a 6, 7, 8 foot drop when they are sledding down the snow, you can clearly see runners on the shield.
Revealing mistake: After the Witch King destroys Gandalf's staff, the wizard and Pippin fall to the ground in the wideshot. In the next close-up, as Pippin (who is behind Gandalf) raises his right leg while he gets up, the white/black sneaker he wears is briefly visible on Billy Boyd's Hobbit foot. (Extended version). (00:24:10)
Revealing mistake: When the Black Pearl swings alongside the Interceptor for the battle, Elizabeth shouts, "Fire all!" The next shot is from behind the lit cannon which is aimed at the Pearl and the following shot faces the Interceptor's cannon, as it goes off. In the shot facing the Interceptor, the raw wood scaffolding type beams are perfectly visible at the entire lower part of the screen, where the painted planks (below the gun ports, above the bilges) of the hull should be. (This is only visible on the video version.)
Revealing mistake: When Fletcher is beating himself up he goes into a stall and squishes his head with a toilet seat. You can see that the white part underneath is made out of foam because it keeps squashing down.
Revealing mistake: When Tim Allen startles Santa Clause and he falls off of the roof, Santa's foot kicks up a blanket that was used to look like some snow on the roof. (00:14:10)
Revealing mistake: When Woody falls out of the closet wrapped in the string lights he hears Buzz's voice, and in the next shot as Woody sneaks up to Hannah's room we see Sid's open door and doorway, which looks perfectly normal. However, after Woody rescues Buzz from Hannah's tea party they both stop in the hallway, and there's another shot of Sid's open door and doorway, only this time it's not normal to say the least. Five of the six hasps, bolts, and locks that should be (and normally are) screwed into and attached to the inside of Sid's door (one hasp mechanism, third one down from the top, is attached to the door's frame) are now actually kind of floating there in mid-air right beside the doorway, as if there's an invisible door there. Weird that Pixar artists deliberately did this, but it's bizarrely funny to see.
Revealing mistake: When Louis is trying to get Gage off him near the end of the movie, as he's struggling in a few shots you can plainly see it's not really Gage but a dummy made to look like him. Looks like a doll. (01:33:35)
Revealing mistake: In the library scene when Richie sees Pennywise the clown, all the balloons filled with blood are popping on people who aren't supposed to be able to see them, but one lands on a lady and you can see her jump as the balloon pops.
Revealing mistake: Mr Hyde makes no bubbles when growling underwater. (01:11:30)
Revealing mistake: In the visions of Nefertiri scene where Nefertiri is fighting Anck-su-Namun back in ancient Egypt, Evie (Nefertiri) gets knocked to the floor and when she lifts her mask up you can see on her right index finger is a band aid/plaster. Did they have plasters back in ancient times? (01:07:49)
Revealing mistake: When Yoda knocks Darth Sidious backwards over his chair, you can see the stuntman's hand. Sidious's hands are old and his nails are dark around the cuticles, but the hand during the flip is perfectly healthy and a different size. (01:45:35)
Revealing mistake: When Brom (disguised as the horseman) throws the jack-o-lantern at Ichabod, there is a shot from Ichabod's perspective showing the jack-o-lantern flying toward him. It jiggles from side to side, revealing it was travelling on a wire.
Revealing mistake: When Inigo and Westley are duelling, they are making athletic jumps. One does it after the other and when they land you can see the mat wrinkle under the "dirt" on the ground.
Revealing mistake: Just after Harry attacks Snape at the Shrieking Shack, he insists on knowing about Peter Pettigrew. In the next shot, as Lupin says, "He was at school with us. We thought he was our friend," there are wedges under the wheels of the piano, however, in the following shots they're gone. (01:34:10)
Revealing mistake: When Qui-Gon, Jar-Jar, and Padme are eating at Anakin's house, Anakin's mum pours water for Qui-Gon. But when she gets to Jar-Jar, she tips the pitcher but no water comes out. (00:39:10)
Revealing mistake: When Captain Needa is killed by Darth Vader because they lost track of the Millennium Falcon, in the background, two guards come to take him away. You can clearly see the dead captain get up almost by himself. (01:10:50)
Revealing mistake: In the part in the motel where THING is doing morse code on the table to Gomez you can see the cut-out in the table where the guy's hand is sticking through the table.
Revealing mistake: It is not what is seen here that is the problem, but what we don't see on the Hogwarts Express; first on the way to Hogwarts when Harry, Ron, and Hermione are in their compartment talking about Draco, and second, during holiday break, when Harry and Ron are talking about Unbreakable Vows. As the camera faces the large compartment window, we see the scenery out the window, but as the train speeds along, the scenic reflection of the windows opposite it, in the corridor, should be seen but isn't. What is reflected is the light colored wall of the compartment beneath the blacked-out window. The camera filming the shots from this angle is positioned at that window, and to hide the camera/crews' outline, the window was covered.
Revealing mistake: After Nuclear Man destroys the cab's hood, the shot changes and there's a thick string running behind him all along the car, and the cab driver is stretching out to pull it. Probably he was activating some sort of bad FX.