Continuity mistake: When Red finds the metal box he takes out an envelope in a plastic bag, folded up on the right side. When he opens it the crease is on the left side. He hasn't turned it over. (02:07:30)
Continuity mistake: When Red is walking along the beach before he meets Andy his hat flies off and almost lands in the water. In the next wide shot the hat is lying a few meters inland against the direction of the wind. (02:10:30)
Factual error: In the courtroom scene there is a microphone - a 1955 Shure SM55. The courtroom scene was set in 1947.
Continuity mistake: The "A" that Andy carves initially is different from the "A" shown near the end of the movie showing how he escaped.
Continuity mistake: At the start when Andy opens a bottle of alcohol, he drinks it with the same hand he opened it with. His hand is shifted after the second time we see him take a drink. (00:03:00)
Suggested correction: Watch carefully he takes the cap off and palms it in his right hand and as he does, so he lowers his hand and grabs the glass bottle to have a drink.
While the mistake isn't very clear, this mistake seems to be about the second time we see him take a drink, after the cut. After he says it's inconvenient the gun was never found, he's seen lifting the bottle by the neck, then the next shot, he's holding it further down.
Continuity mistake: When Norton prepares for his suicide you see on the desk a photograph and, a bit away, a lamp. After he has shot himself the photograph is leaning against the lamp (it was too far away in the previous shot to have fallen against it). There's also some sort of card open on his desk on some paperwork which suddenly moves onto bare desk and gets shorter. (01:57:10)
Factual error: In the scene where the guys are drinking beer on the roof, the bottles have "ribbed" tops. Beer bottles did not have twist-off's in the late 40's.
Visible crew/equipment: When Sgt. Hadley nearly throws Andy off the plate factory roof, the reflection of a boom mike is briefly visible in the shiny brim of Hadley's hat. Andy dropped the tar mop before approaching Hadley, and there are no other objects in this shot that could have caused the reflection. (00:35:00)
Continuity mistake: When one of the "sisters" gets beaten up by Capt. Hadley he tries to escape from his cell and holds on to the bars on the other side of the passage. From the side his right hand grabs a diagonal bar, but seen through the bars he is holding on to a vertical bar. (00:43:15)
Factual error: Red, while using the restroom in the grocery store he worked in after getting out of jail, is peeing in a 1980s urinal.
Continuity mistake: When the convicts are having beer on the roof you see Red taking a sip. The camera cuts to Heywood offering Andy a beer, and when it cuts back to Red taking the next sip his bottle is much more full than before. (00:36:55)
Factual error: When Red is working in the grocery store after his parole, as a bagger, the cashier is using a National C100 register, which is a non-itemizing register. This wouldn't be usable at a checkout in a grocery store, as the customers usually have multiple items.
Other mistake: When the cons are drinking beer on top of the roof, the man that finished his bottle gestures for another. The guy takes out an already-opened bottle of the bucket horizontally, the beer should've poured out.
Suggested correction: The bottle is only horizontal for a second as he lifts it; enough time for some of the contents to pour out but not all.
Continuity mistake: When Andy is talking to Red for the first time in the yard, Red is playing catch with a few guys. Towards the end of the conversation Red catches the ball twice without throwing it back the first time. (00:25:00)
Factual error: The sign for Buxton is horizontal with two poles. Signs for Maine towns are vertical and mounted on a single post.
Continuity mistake: During the scene where Andy and Red meet for the first time (baseball scene) the sun is in Red's face and so, Andy shouldn't have the sun in his face. But in fact, sometimes Andy has the sun in his face and Red doesn't anymore. Either they move very quickly between scenes or (probably) the whole scene were filmed at least two times. (00:24:00)
Revealing mistake: In the scene where Warden Norton is loading his pistol, as he dumps out the bullets and loads them the primers are dimpled. Unfired bullets would not have the dimples from the gun's hammer (even if they were home made reloads, the primer would have been replaced).
Continuity mistake: When the warden shoots himself, he places the gun on the middle of his neck but when we see him lying there the bullet hole is now on the left side. (This is corrected on the tenth anniversary edition. The director also confirms this change on the DVD commentary.) (01:57:00)
Continuity mistake: In the same scene where Brooks is hanging himself, he carves his name and he is almost eye level with the spot where he is carving his name. The place where the rope is tied is lower. How come when he finishes carving his name he stretches to put the rope on? It is lower than where he was carving his name. (01:00:25)
Revealing mistake: When Tommy crumples up the test paper he had written for Andy and throws it into a waste basket the metal container shakes as if he had thrown something heavy. (Telling from the noise it makes the item must have been heavy.) (01:23:30)
