Enhancing Motion Picture Lens Performance by Digital Calibration and Correction

To some degree, all lenses used by the motion picture industry exhibit certain distortions which can detract from the ideal viewing experience. This paper presents a lens calibration and correction system which enables these problems to be resolved digitally in post production. — For some time lenses such as the Cook 4i and now 5i provide the necessary metadata on focus and aperture settings to enable digital post corrections to be applied. Cameras such the Alexa and RED are capable of capturing this metadata. Many other lenses however may be adapted to provide the necessary metadata by means of a simple encoder. The paper presents how this is achieved followed by a presentation of the digital correction system for enhancing such scenarios as extreme focus pulls. Using digital high definition camera systems the calibration of each individual lens is presented along with the automatic derivation of the required lens database. The full post production work flow through to final image generation is presented.

Published

2010-10

Content type

Original Research

Keywords

Lens distortions, Lens breathing, Barrel distortion, Focus pull, Lens correction, Digital correction, Metadata

DOI

10.5594/M001356

ISBN

978-1-61482-944-7