Revealing mistake: When Wyatt Earp and the actress, whom he marries later in the movie, meet on horseback, they go on a fast paced ride that concludes after going down a steep hill. If you look at the actress' feet, you will see she is riding side-saddle - a very difficult feat considering the riding they do. If you look closely you can see her real leg, safely on the other side of the horse. The side-saddle leg must be fake.
Revealing mistake: While in the convenience store, watch the arcade screen the punks are playing, they are getting very excited about the game, however anyone who has played Street Fighter 2 will notice that they are merely looking at the demo version and even the words "insert coins" are displayed on the screen.
Revealing mistake: Doesn't it seem odd to anyone that the crops hadn't been reaped by Thanksgiving in South Dakota?
Revealing mistake: In the final scene when Annie and Sam are exiting the observation deck coming towards the elevators, the New York skyline backdrop which should be visible behind them is missing, and the entire sound stage wall can be seen beyond the observation deck safety railings instead. 'Although the exterior and lobby of the Empire State Building, 350 Fifth Avenue at 34th Street, are the real thing, a slightly larger replica of the Observation Deck was built in a hangar at Sand Point Naval Base on Puget Sound just northeast of - where else? - Seattle.' https://www.movie-locations.com/movies/s/Sleepless-In-Seattle.php. (01:39:35)
Revealing mistake: When Phil drives the truck off the cliff, you can see right through the grill of the truck (meaning there is no radiator or engine), and the transmission is also missing, as you can see when the truck is falling upside down. Without an engine or transmission it would be hard to drive off a cliff.
Revealing mistake: After Naomi is thrown from her balcony in the beginning, the blood on her face has beaded down her face and is staining her blouse. This is impossible being that the injuries she received happened less than a second before and she landed face down after going through the glass, so the blood couldn't have ran down her face in that direction.
Revealing mistake: When Ada and Baines leave the island the Maoris pull the heavy canoe with the piano on top across the beach into the water. From the tracks in the sand you can tell that it runs on wheels. (01:44:35)
Revealing mistake: When the cab skids off the road and down the hill you can see that it never actually hits the tree - it is yanked back with about a decimeter left to go before it would hit.
Revealing mistake: During the opening credits, it is obvious that the train is just a model during the initial close up shots.
Suggested correction: There is nothing in the opening shots that betray it as a model shot. Logic alone argues against it. Why would they go to the expense of building a detailed model when there is no unusual action or angles required? Especially since many of the shots are obviously not a model. Exactly how is it obviously a model?
I agree it does look like it's a model train, but that's only because of the filming techniques that make it appear to run a little choppier like it's was a light weight model. But it's real, for example in one scene that looks like it's a model, you see a real bird flying on screen.
Revealing mistake: When Ryce is talking to the vet on the phone, the vet would have to be talking extremely fast because of how little time there is between Ryce's questions.
Revealing mistake: When Jack comes into the bedroom right after Laurel has delivered the baby the mother looks as refreshed as if she had just woken up from a nap, and the baby is much to smooth for a newly born. (01:05:25)
Revealing mistake: When Alabama sets fire to Virgil's head and you see him stumble out of the bathroom, his head is greatly disfigured and larger, indicating the fire protective mask.
Revealing mistake: When Porthos shoots the assassin with a crossbow, he is a good distance below him. But when you see the assassin grab the bolt, it is straight in his body as if he'd been shot level.
Revealing mistake: When Gilbert finds Arnie in the bath and takes him out, you can see a towel around Arnie's waist.
Revealing mistake: Charlie is hanging off the ledge of the hotel when Rose chops the axe in between his fingers - if you look closely at his hand it clearly looks like rubber.
Revealing mistake: Toward the end of the movie when Van Damme is on the motorcycle watch the pull back shots. You can see the stuntman in place of Van Damme. In addition, the stuntman is clean shaven in some shots where Van Damme looks like his beard is growing in. It's very noticeable, especially when he goes down the mountain. You can even see the ramp set up as he first goes down.