Continuity mistake: When Vader's shuttle is approaching the Death Star, the crew in the control room of the Death Star are wearing black gloves. One of them then reaches forward to press a button, but in the close-up of his hand pressing the button, the hand is not wearing gloves at all. This can only be seen in the widescreen version. (00:02:25)
Visible crew/equipment: When Superman is landing to stop the plough machine, the wires holding him are visible.
Continuity mistake: As Arnie runs after Leigh at the drive-in, he arrives under the awning with his hair slightly wet, but still rather full-looking. But in the next close-up, it's soaked flat onto his head. (00:45:40)
Continuity mistake: When the doctor on the right walks in the operating room he puts a glove on. A shot later it's off and he's putting it again.