Best sci-fi movie mistakes of 1969
Revealing mistake: Early in the film Gene Hackman tests a rocket-powered backpack outside the space station. He slowly spins sideways through a complete circle, but instead of each side of his body being lit up in turn as it's pointed towards the sun, the light stays constant throughout the maneuver, showing that the makers just took a photo of Hackman and rotated it.
Continuity mistake: Frankenstein buys a sprig of freesias as a buttonhole: two yellow flowers and a purple. The sprig immediately changes into two purple flowers and a yellow. When Frankenstein meets Mrs Brandt and they go into the drawing room, the flowers are two purples and a red with yellow centre. Once in the cellar to see Mr Brandt, the red goes, and a yellow is back with two purples.