Revealing mistake: In the final Indian chase at the conclusion of the film, when a covered wagon rolls over, one can see the rope that was used to ensure it tipped over.
Revealing mistake: When Shane punches Chris in the bar, you can see that Shane's fist actually misses Chris' face.
Revealing mistake: In the first scene of the crashed meteor, on the extreme left of the scene where the smoke is, it seems to be billowing up from behind a stage wall, as there is a definite vertical line and a gap between the smoke and the left edge of the frame.
Revealing mistake: As the spaceship heads back into space, it leaves the same way that it crashed - they reversed the film. (01:18:30)
Revealing mistake: In the scene where Lancelot runs into and fights Arthur's ambushers, he runs one of them through with his sword. It is visible that he stabs his opponent past the body, but close enough for the appearance.
Revealing mistake: When ice is shedding from the plane's wings, the chunks slowly slide forward and then down the leading edge. Loose chunks should have flown off rapidly to the rear due to the airflow.
Revealing mistake: When the smudge pot is set off, it's on the ground, smoke coming of the ends. A moment later, along with a huge cloud, if you look at the bottom of the scene, there's an area about five feet wide billowing smoke.
Revealing mistake: During the outdoor party at the Rainbow Cabins Marilyn asks the DJ to play "Kiss" in order to drive her husband George nuts, and after a couple of minutes he comes out and smashes the record. As he walks back to cabin B it's obvious this is a set as there's nothing inside the room except a blank wall. (00:20:15)
Revealing mistake: In various scenes before the Compass Rose is supposed to be fitted with radar, it's obvious the 'lantern' round the already fitted radar aerial has been removed and the aerial itself covered with a tarpaulin to simulate the ship in its earlier, pre-radar, state.
Revealing mistake: When Nicky is taking a shower in the trailer, on two different occasions you can see the beige colored towel that is wrapped around his waist.
Revealing mistake: At the end, when King's troops are attacking Khan's camp, a "dead" insurgent hops up and runs off screen just as the arsenal explodes. (01:36:00)
Revealing mistake: In the beginning where Vincent Price is brawling with his business partner, his partner throws a pipe or bar at him. Price ducks and the bar hits something that the camera was connected to, because the scene jerks.