Filmed in Genuine Field-Sequential 3D: The movie was shot in 35mm using Chris Condon Stereovision lenses. These lenses utilize a 3-D filming technique called "over and under." During filming, a normal 35mm film frame is exposed by two lenses (one for each eye view) instead of one. The top half of the film frame is exposed by one lens and the bottom half of the frame by the other lens. Hence, the name "over and under."