Revealing mistake: When they get back from Bunyans and the garbage is on the floor, Chet runs to the bathroom. The family and Roman follow him, you see Dan do a 3 count for everyone to run back In screaming, the blocking of that shot included a gap that you could see them off camera right.
Revealing mistake: While Akeem is getting his hair cut, you can see the reflection of the white character he plays in the mirror. It is quite obviously a stand-in, with a fatter face and different glasses. (00:33:45)
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: When the weasels are at Eddie's apartment and Roger is handcuffed to Eddie, Roger runs under the bed and drags Eddie on the floor. As he pulls him you can clearly see a board with wheels under Eddie that is pulling him under the bed. (00:38:50)
Revealing mistake: When they show Heather Chandler in her casket in the funeral scene and everyone is praying, she's clearly breathing.
Revealing mistake: Adam and Barbara aren't supposed to have reflections, but when they enter the recreation of their home (just before they meet Juno), their reflections are shown perfectly in the glass display case that holds Delia's sculptures, behind them. (00:32:55)
Revealing mistake: When Charlie and Daisy get the flat and have to hitch-hike, and Daisy takes off her shoes to run to the car that has stopped, the bottoms of her feet are already filthy (presumably from having to do the scene over and over).
Revealing mistake: When Les' mom is doing the laundry and "finds" the Test Failed notice, you can see that she actually had it in her hands the entire time. She transfers it from one hand into the other, then puts the hand with the paper into the pocket and pulls it right back out, then knocks it off onto the floor, and acts surprised.
Revealing mistake: When Hightower throws his frisbee to Proctor and sends him flying, Proctor starts flying away before he catches the frisbee.
Revealing mistake: One of the reindeer's "power-up" lights turns on before its name is called.
Revealing mistake: When the window slams on Nordberg's hand it is that the window stops right above his hand. When he pulls his hand out the window doesn't go all the way down and a wooden cube is visible on the edge of the window stopping it from closing. (00:06:50)
Revealing mistake: At the beginning of the film, young men headed to basic training in Biloxi, Mississippi are shown on a train crossing a river. The name of the train is visible and easy to read. At the end of the film, the men are leaving Mississippi. The scene shows the train crossing the same river, but the name of the train is backwards. The director must have wanted to save money, and reversed the film for a mirror image.
Revealing mistake: Penny is held captive in her bedroom, the window covered by bars. Seaweed shows up to 'rescue' her, brandishing large wire cutters and clips the bar on her left, but you can see the bar on her right is pre-cut as he bends both, just before she climbs out the window.
Revealing mistake: None of the grenades Nick throws at the bar does any damage.
Revealing mistake: When Jackson jumps on top of the cab to catch Tony's killer, you can see the handles on the roof that the stuntman is holding on to so he doesn't fall off.
Revealing mistake: When the kid who breaks the egg throws it out the window, the egg hits another egg which starts rolling down. You can see the tracks on the grass making it easier for the egg to roll. (00:30:05)
Revealing mistake: At the end of the movie when Josh and his friend are walking down the street, a lady crosses the street in front of them. Look closely to the left of the screen. The lady is obviously behind the tree waiting for her cue because she is not seen walking toward the tree before crossing the street. (02:06:40)
Revealing mistake: When the twins first meet in the forest, they do so by running into each other then saying "I see me." Right before they crash into each other, they both put their arms up slightly to brace for the impact.
Revealing mistake: After the shootout in the hotel, the police photograph the bodies of the dead cleanheads. The flash of the camera causes the "dead" men's eyes to blink slightly.
Revealing mistake: The "Great Train Robbery" actually took place on a two-track railway near Cheddington - the West Coast Main Line. However, the filming took place on the Great Central Railway steam line near Loughborough, which only had one track at that time. They laid a second track for the filming, but omitted to cut down a large tree at the end of the rails, which would block the path of a train. This is blindingly obvious, especially as they show this "atmosphere shot" twice. The tree is still there the second time.