Photographic Duping of Variable-Area Sound

Release print laboratories require a method of quickly making photographic duplicate negatives to replace damaged original negative sections. — The paper shows the development of a method of making dupes which have the same optimal print densities as the original negatives. A selection of film stocks is first made using the ratio of transmission between black area and fogs as a “yardstick.” Processing data are shown in a family of curves, and the “best operating point” for the entire process has been determined. Fog considerations have been carried throughout the process. — An outline of commercial practice is given together with the necessary routine tests.

Print ISSN

0097-5834

Published

1940-01

Content type

Original Research

DOI

10.5594/J00023