Revealing mistake: When Sonny is punching Carlo under the spraying fire hydrant, he misses an audible punch by at least six inches. (01:43:30)
Revealing mistake: Although the film is set during the aftermath of the Mexican War (1848-50), the mountain vistas display some lovely radio towers and fire ranger stations.
Revealing mistake: In a scene where the canoes are shooting the rapids through a sheer cliff you can clearly see a stuntman climbing out of the water onto the rock.
Revealing mistake: In the early part of the chase scene, when the person hanging the banner swings into the pane of glass, you can actually see it start to shatter before he touches it.
Revealing mistake: When Stan is in the safari park driving the bus with the monkey on the steering wheel the scene outside the bus is obviously background projection and at times it runs backwards giving the impression that the bus is in reverse when all the time it is going forwards.
Revealing mistake: When McDonald is in the tunnels and is called to pick up the phone, he picks up a red phone. It is a standard Bell TouchTone desk phone. To make the phone look more futuristic, there was no cord and it was disguised as a cordless phone. The port that the cord would plug into is covered by a piece of colored tape. This also can be seen in the operations center of Ape Control when the worker picks up the phone.
Revealing mistake: When the ship is upside-down and they're trying to get Susan down from the table, you can see that the table really isn't attached to the ceiling. You can see the center pool split into legs that are supposed to be connected to the floor, but when Susan moves around and shakes the table, the legs shake and you can see space between them and the floor. Even if the other legs outside of the shot were connected, the table would be leaning under Susan's weight.
Revealing mistake: When Weasel says, "How's your back, baby?" to Phyllis, she spits in his face, but Weasel closes his eyes before she spits.
Revealing mistake: Freeman Lowell has several cargo containers dumped off the spaceship, to make it appear the ship has suffered an accident. A wide shot shows the ship receding in the distance, with the containers rolling weightlessly in the foreground. As the foreground containers pass slightly in front of the more distant ones, they don't mask them; their images overlap. The containers were apparently composited into the shot with simple multiple exposures. (00:35:40)
Revealing mistake: When the cafe owner takes Mike's chef hat away from him to continue frying the food on the hot plate, he stands on Mike's hand and breaks an egg. You can see that the egg is a fake one as no yolk is visible.
Revealing mistake: At one point when the soldiers are walking through the jungle, one of them steps into a trap and is pulled up into the trees to be killed by Indians. However, if you watch this scene carefully, when the soldier (who steps into the trap) walks into frame you can see a wire already attached to his foot leading up into the trees. He doesn't step into a trap. (00:22:26)
Revealing mistake: When Itto puts the cover on the baby carriage it's obvious that the sudden downpour of rain is just a sprinkler placed in front of the camera. Pay attention to the cover, Itto's clothing and the puddle behind the carriage, they remain completely dry/untouched. (00:11:00)