Visible crew/equipment: After Ripley fails to shut off the auto destruct sequence, she runs through a corridor filled with gas. As she exits from the gas right before the shot cuts away we see her pass by a full sized light. Beside this light is the clear arm and head of a lighting crew member. (This is acknowledged on the DVD commentary).
Visible crew/equipment: After Reggie touches the metal poles, he goes flying backwards. As he hit's the floor, you can see a thick white rope attached to his left foot. (01:11:10)
Visible crew/equipment: Young vampire Danny floats away from the window after being confronted with a crucifix. The effect is quickly ruined when the boom he is sitting on can be seen moving him for 8 seconds. (01:43:40)
Visible crew/equipment: When the real estate lady is showing George and Kathy the rounds of the house, the studio lights are in the reflection of her glasses.