Cinema Projection Distortion

This paper addresses projected image distortion in a cinema setting. Several types of distortion are defined and examples are presented to show that the degree of distortion in the image can be calculated based on theater geometry as well as film format and projector lens specifications. This paper concentrates on inherent distortion values that typically affect the overall shape of the picture area and the relative shapes of all subjects being viewed, as well as the audience's perception of imaged picture quality. Since distortion changes only the shapes of objects in the picture and not how well the viewer can see them, there is little basis for objectively derived design limits. Further, when viewing a real scene that does not contain a perfect rectilinear test grid, the eye accommodates small amounts of distortion, which is therefore not perceived. However, moderate to severe amounts of distortion, and particularly distortion in memory objects such as curved horizons and leaning or curved flagpoles, is disturbing to viewers.

Print ISSN

0036-1682

Published

2000-08

Content type

Original Research

DOI

10.5594/J05273