Revealing mistake: During the chariot race, where the contestants are riding towards the screen, tyre tracks from the camera vehicle are clearly visible imprinted in the sand. (00:20:50)
Revealing mistake: When James Bond has a spider on his arm, one can see he's under a glass plate, and the spider on top of the plate. (00:41:55)
Revealing mistake: When the Hudson Ferry captain casts off the large label that reads "Hudson Ferry" is on his left side of his jacket. However, in the exterior shot as he looks out the window at the whirlpool, the label is on his right side. This shot was flipped, and amusingly, the CGI guys actually retouched the words "Hudson Ferry" so it wouldn't read backwards. (01:02:25)
Revealing mistake: After Toad spits his slime at Jean Grey he falls to the floor. You can see the tether that was holding him in mid air. (01:13:55)
Revealing mistake: When Cody is on the jet ski inside the evil guy's hideout, he smashes through some glass. The glass smashes before the jet ski even touches it.
Revealing mistake: During the big underground fight scene, the solid rock wall moves as George pounds a Morlock's head against it.
Revealing mistake: In the last third of the film just after the announcement that Kong is coming, a native jumps out of his hut, loses his balance and falls by a chicken coop. His wig comes off and gets caught on the fence.
Revealing mistake: At the zoo, Harry looks to his right, at the 'bred in captivity' sign of the Python. In this close-up, the green plant that is below, to the side of the exhibit sign, is protruding out past where the glass supposedly is, yet this is BEFORE the glass disappears. As a matter of fact, this plant, nearest the exhibit sign, changes its position considerably throughout these shots. (00:06:50)
Revealing mistake: While driving the red truck through the rolling house, Dorothy is mounted on the back of the truck. There are some very sensitive and fragile instruments located on the top sides of Dorothy that stick up above the cab of the truck. These would certainly have been torn off while crashing through the walls of the house, turning Dorothy into a useless pile of junk.
Revealing mistake: When Sandman is in the truck of sand and the cop climbs up to catch him, you can see the edge of a platform uncovered. The platform is clearly there so the cop could walk without sinking - he stops right where the platform ends.
Revealing mistake: Near the end of the film, when people are running in terror out of the theater and into Times Square, you can see that the people are not leaving any footprints in the snow. The snow must have been digitally added to the scene.
Revealing mistake: When Sarah is making her way to the baby Stego, just before she gets on her belly and crawls closer to it, you can see the kneepads she has on.
Revealing mistake: When the Enterprise is leaving space dock, look at the right (starboard) side of the ship. You can see the shape of the mounting arm the model was mounted on, even though it was blacked out to look like space, and it also blocked out the bottom of the dock. The footage was reused from Star Trek: The Motion Picture.
Revealing mistake: When the crew are getting ready to load up the gold, one of the crew slams the crate lid making the gold bars "move".
Revealing mistake: When they are burying the Swede on the beach, you can see him blink when they throw sand into grave.
Revealing mistake: When Tim Curry runs out of Kevin's hotel room after being scared by the inflatable clown doll he hits his knee on a table. When he hits the table and then hops away you can clearly see that he is wearing a knee-pad.
Revealing mistake: The Aspen lift operators are wearing Copper Mountain uniforms. Copper Mountain is in Colorado, but it is over two hours away from Aspen.
Revealing mistake: After Pola Ivanova sneaks out of the baths, she climbs into the car with General Gogol, who can be seen to be a double and not Walter Gotell. (01:07:20)
Revealing mistake: During the draining of the water in the dish, some shots show the water moving backwards. For instance, at a particular moment, masses of water jump up, arc toward the opening, and fall in it. The most likely reason is that, during the filming, the special effects people took a shot of a replica of the dish filling with water, then edited it the other way to show that the water was emptied from the dish. (01:42:00)
Revealing mistake: When Madame gets off the carriage, Frou-Frou winnies to get her attention. Madame then proceeds to feed her. Frou-Frou eats from her hand. However, if you look closely at Madame's hand, it is empty. (00:03:05)