Visible crew/equipment: After Ivan shoots the bird with the arrow, he takes one of its feathers and throws it. As it sails across the screen, the wires making it float are plainly visible. (00:19:15)
Visible crew/equipment: When Prof Fate sends the torpedo after the Great Leslie at the water speed record attempt you can see the wire just under the water pulling the torpedo towards Prof Fate's car when it detects his cars' exhaust explosions.
Visible crew/equipment: When the cars arrive at the mansion after attending the funeral, one of the car doors opens, and the film crew's lighting equipment is reflected in the door.
Visible crew/equipment: When Doctor Zhivago comes home after that trolley ride in which he and Lara pass each other without notice, he enters a glass vestibule in the house. As he opens the glass door, you'll see the reflection of a man's face in it. The reflection bears a close resemblance to David Lean, the film's director.
Visible crew/equipment: Throughout the movie, if you watch closely you can see the zippers on the backs of the Eye Creatures' costumes pretty easily.
Visible crew/equipment: When it is the just the Medical officer and the Sargent Major in the cell after Williams has sent them to the showers: the M.O walks from the door to sit on one of the beds, as he turns to sit down the shadow of the camera man is cast on him.
Visible crew/equipment: In the final scene where Frankenstein is fighting the Spacemonster on the spaceship, there are upshots of the monster attacking to make him look larger, but looking right behind his head you can see a ceiling mounted fluorescent light and electrical conduit; neither of which would have been on a spaceship.