Revealing mistake: At the start, when Data is being pulled towards the chained orange drum, due to the angle of the close-up, we see that the soles of Data's Nikes are not actually touching the ground (since there is a rolling mechanism under his feet). Despite the fact that Data is quite inventive, we see in the next shot there's nothing attached to Data's Nikes. (00:03:55)Super Grover
Revealing mistake: Whenever Marv is outside walking in the snow in his bare feet you can tell that the feet aren't real.
Revealing mistake: In the final game against Iceland scene, there is a point where you can see that the people in the stands are actually cardboard cut-outs.
Revealing mistake: In the Forbidden Forest, HRH are introduced to Grawp. Just as the giant lifts Hermione off the ground, in the shot from behind her, Hermione's legs disappear below her calves; the digital lines are actually visible. Slow-mo is not necessary. (Only visible on fullscreen DVD.) (01:29:40)Super Grover
Revealing mistake: When Troy says "I'll sing with her," Ms. Darbus turns around "in response" to his voice before he even says anything.
Revealing mistake: When Hallie trashes Annie's cabin and the huge water balloon is about to fall on Annie's head, the camera is at a downward view and Annie clearly steps into the trail of the balloon instead of jumping away. (00:18:05)
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)Super Grover
Revealing mistake: After Carmen rescues Juni, as they fly over the city she says, "Hang on butterfingers." In the following close-ups, where is the handcuff with the broken chain on Juni's wrist? He is not wearing it on either wrist in any of these close-ups. It's obviously back in the following shots. (00:41:45)Super Grover
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.Super Grover
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: The oil lamp carried by Mary when she first finds Colin has a flame that never flickers, and is likely an electric lamp.