What is a 3-D film?

A 3-D film is any visual presentation system that attempts to maintain or recreate moving images of the third dimension, the illusion of depth as seen by the viewer. It involves filming two images simultaneously, with two cameras, filming at 90 degree angle via mirrors. When viewed in such a way that each eye sees its photographed counterpart, the viewer’s visual cortex will interpret the pair of images as a single three-dimensional image. Modern computer technology also allows for the production of pseudo-3D films using CGI and without the need for dual cameras.