Continuity mistake: When they are looking at the house and they get out of the car, the one man on the passenger side leaves his door open. When they walk to the side of the house and come back to the front, you can see the car in the background and the door is shut.
Factual error: The lake that Jack told Rose he went ice fishing on when she was threatening to jump is Lake Wissota, a man-made lake in Wisconsin near Chippewa Falls (where Jack grew up). The lake was only filled with water in 1918 when a power company built a dam on the Chippewa River, six years after the Titanic sank. (00:39:05)
Deliberate mistake: Leaven spends too much time thinking about if 645 and 372 are prime numbers to be believable. But she knows the factors of 649 and the result of 26 to the power of 3 almost immediately. Plus anyone with any maths knowledge whatsoever would know that any even number (or one divisible by 5) can't be prime, so 645 and 372 could be dismissed without even thinking about it.
Continuity mistake: Just before Demi Moore is about to get her head shaved she sees the base commander about equal treatment, and we notice very visibly that O'Neil has one side of her face bruised and all red and swollen. But in the next scene, which takes place moments later, when O'Neil is shaving her head, her injuries are all gone. Where did they all go to?
Visible crew/equipment: The cameraman is visible in the reflection of window while Holden is walking back to his car in the rain.
Factual error: The plastic explosive used on the cockpit door was C-4. When shot (as shown), C-4 does not explode; it requires the use of a detonator.
Suggested correction: You can see him applying a detonator prior to him shooting it.
If he applied a blasting cap (detonator) he should have used it then. Just putting a detonator into C-4 doesn't all the sudden make it vulnerable to being shot, he would have to actually hit the blasting cap's wire, which is about 5mm thick and relatively short (and it would have to be one that's sensitive to gunfire). Not a very probable shot, even less so when he doesn't even look when he shoots.
Plot hole: In the scene where Ashley Judd runs away from her attacker and falls into her aquarium he has moved to the bottom of the stairs - there is no way he would have been able to move that full fish tank. It looked to be about a 30 gallon tank - it would weigh about 400 pounds with the stand and even if he slid it with some superhuman strength, glass tanks are notorious for shattering when you move them full. Plus it would've made enough noise to wake the dead - no way she wouldn't have heard it.
Continuity mistake: When the kid rescues Bud from his former owner, Bud's paws become all muddy when the faucet breaks. In the next scene they are running down the road and Bud's paws are clean.
Visible crew/equipment: In the shoot 'em up scene at the hangar near the beginning of the film, right after Tito and Wanda take down Pollux, when Troy shoots an agent in the stomach and the agent flies back - you can see at least two cable wires pulling him backwards. You can first notice the 2 wires when the agent is running in slow motion right before he shoots him. (00:14:15)
Continuity mistake: When Lolita begins to undress in front of Humbert, she is wearing her school uniform. Her shirt first appears tucked in, then out and then in again.
Audio problem: When Chris drives up in the truck while Selena is mowing the lawn, Selena asks what he got. While you hear "junk food" his mouth says something else.
Factual error: In the beginning of the film, the Dowager Empress Marie states that the year is 1916 and that they are celebrating the 300th anniversary of their family's rule. The 300th anniversary actually took place in 1913. (00:01:05)
Other mistake: When the slaves are getting into the Portuguese ship (the "Tecora"), the crew shouts in clear Spanish (some Spaniard and some Mexican accent) rather than the expected Portuguese. (01:18:10)
Factual error: The geography around the VLA in New Mexico is actually relatively flat - in fact one of the reasons why the array complex is there is because the land is flat. The canyon in the film was actually Canyon de Chelly, in Arizona, more than 170 miles (270 km) away. But in the film, when Ellie goes to the canyon, the radio antennas seem to be right there, insinuating that the canyon is part of the VLA's magical desert scenery.
Continuity mistake: In the scene where the town folk are having an outdoor festival, Steven Seagal is invited to play with the band. An older gentleman hands him a guitar with nylon string tuners (open headed classical type) but when he takes it from him, it is a Steel string Martin Acoustic (solid headed flat top) guitar.
Continuity mistake: Pay attention in the beginning of the movie, when Ordell is showing some "girls with guns" to De Niro. While he suggests to run fast the tape, he presses the REWIND key. The expected one would be the FF key. (00:04:25)
Visible crew/equipment: When Ethan Hawke is picking out a suit and shoes, you see a distinct hand on the left side of the closet holding up what must be a false wall. (00:33:25)
Visible crew/equipment: The camera searches for Dora whilst Guido plays music through the open window. In her room, you can easily see a cable (from a microphone or a spotlight?) on the left side of the screen. (01:42:00)
Visible crew/equipment: Near the beginning, when the new kid (Scott Bairstow) first goes to biology class, after roll call, he is talking to another character and you can totally see the boom mike. The whole microphone is in the shot.
Continuity mistake: In one of the scenes Hopkins is trying to make what I think is a fish hook or something. He's obviously been in the wilderness for a while so he's not clean shaven but he isn't exactly beardy either. However, during the scene with this fish hook his beard changes from moderate to bushy to moderate again within seconds.