Other mistake: Murphy lands the helicopter on a railway line so an oncoming train will destroy it completely, and this happens exactly on cue with huge, dramatic explosions and flying debris. Apparently the train driver doesn't think this is important enough to interrupt his busy schedule - he doesn't stop the train. We do not hear brakes being applied - the wheels would make a noise like the sky coming down - and the train doesn't slow down at all - it just keeps on going.
Continuity mistake: When Melinda Dillon breaks the lamp, it is broken into many pieces, but when Darren McGavin is gluing it back together it is now in much fewer and bigger broken pieces. Obviously different broken lamps were used.
Revealing mistake: When Luke is being fed to the Rancor, in Jabba the Hutt's dungeon, there are black outlines around the beast's legs, from the composite's blue screen special effect. This was edited out in the special edition rerelease.
Suggested correction: This was not a "mistake". The outlines showing around the beast's leg were due to the limited CGI technology at the time the film was made. With advances in special effects in the following decades, the filmmakers were able to enhance the CGI quality in later releases.
But it is a mistake to show that the Rancor is not real, and the outlines show that. It's certainly not intentional.
Not sure what you mean that the rancor is not real. Of course it's not real. The issue is, at that time, it was not technically possible to show the beastie without the lines showing. I classify a mistake as something that was not intentional. In this case, it was, due to the limitations of CGI in the 1980s.
Factual error: In the balloon scene, it seems like Q can circle around and land on a spot where he flew past previously. A balloon can only fly in the direction of the wind.
Continuity mistake: When Christine is fixing herself after the guys smashed her up, her front end is shown to be perfectly straight for its entire width and the hood is missing. Near the end of the scene, the front end is shown crushed and unfolds again, and the hood appears from nowhere.
Visible crew/equipment: After Mortimer's comment that Billy Ray has probably been stealing since he could crawl, when it cuts to the two officers opening the squad doors to place Billy Ray at the back of the vehicle, the barndoor set lighting is visible over the squad car at the top right corner of the screen. (00:18:25)
Continuity mistake: Near the end of the movie, the panel has JPE 1704 TKS showing, but when Joshua finds the launch code, CPE 1704 TKS is blinking on the screen.
Continuity mistake: When Dally falls off his chair in the drive-in movie theater, you can hear Ponyboy's laughter above them all. When the shot changes to Cherry, you can see Ponyboy with a serious face on in the background but you can still hear him laughing.
Other mistake: Towards the end of the movie, when Superman drops Gus off at the coal mine, Gus begins talking with the coal miners about him and Superman. He then rips open his shirt (as if he had a Superman costume on underneath). How did Gus know that Clark Kent tore his shirt like that in order to change into Superman, or keeps his suit under his clothes at all? The only people who know this fact are the ones who have seen the transformation from Clark to Superman, i.e. the audience.
Revealing mistake: In the early part of the film, Beverly D'Angelo and Chevy Chase check into the hotel/motel. She goes in to take a shower but he barges in. If you look real closely, she is wearing underpants and is not nude although she is taking a shower.
Continuity mistake: In the movie's final moments when Tom Cruise is buying back all his household items, the lady in the cargo bay says "that's everything," except for the crystal egg she throws out into the yard for Tom to catch. You can clearly see many more items left in the truck. But when the truck pulls away seconds later, nothing is left in the cargo bay except our villain sitting on a chair. Where did everything else go?
Visible crew/equipment: About one hour and fifty minutes in, the two stars get into a fight and are rolling around the floor. In at least one scene, a cameraman, with a handheld Panavision camera, is quite visible in the middle of the shot.
Continuity mistake: During the scene with the guys dancing in the locker room, when the coach comes in, you see the same shot of Stefen taking off his jacket twice.
Continuity mistake: When Tom Selleck rolls his plane upside down to dump the Afghan at several thousand feet altitude, you plainly see stationary tree tops at the bottom of the frame.
Visible crew/equipment: When the first deal goes wrong and the man with the chainsaw jumps out the window you can clearly see him land on a grey crash mat because it lifts up at the corners. (00:27:55)
Continuity mistake: Eddie drives a 1957 Chevy convertible off the bridge. A scene showing the car being fished out of the water clearly has an older vehicle dangling from the line.
Suggested correction: The car pulled onto the bridge is absolutely a 1957 Chevrolet convertible.
Continuity mistake: During The Miracle of Birth Part 1, when the guy goes into the operating room, the girl puts the gown on the first doctor. It's barely on, but, in the next, wider shot of him, it's completely on and she's tying the back together. (00:04:30)
Visible crew/equipment: At one point Clint Eastwood is out in the woods practising his shooting with his new .44 auto-mag pistol. While he's doing this, a car pulls up and a black male begins to get out with a shotgun. (We later learn that this is his partner). As the man with the shotgun is opening his door, if you look at the reflection in the car window, you can clearly see the reflection of a man with a camera and another man standing next to him.
Continuity mistake: When Jack kicks the TV it falls backwards, and the screen has snow on it. However, when the repair technician comes in, the screen is broken.
Continuity mistake: When the brunette is in the shower and that boy shows up he is wearing brown pants, but when you see the clothes lying on the carpet while they are in bed together, the pants are blue jeans. (00:59:00)