Effect of Humidity upon Photographic Speed

WHILE it has been known for many years that the sensitiveness of photographic materials falls when the gelatin is allowed to absorb moisture by exposure to humid air and for a few special purposes, such as in astronomical work, precautions have been taken to avoid this effect, it is probably not too widely known among users of cine films that the effect is large enough to be of practical importance under adverse conditions. It was, therefore, thought worth while to present to you some quantitative data obtained in the Redpath Laboratory of E. I. duPont deNemours & Co. showing the magnitude of the effect observed with a variety of materials, more especially since our observations show that the phenomenon is a very complex one. In all cases, the results given are the averages of a number of careful independent determinations and it should be stated that equilibrium was not considered to have been attained until the films had been exposed to the various atmospheres for at least 24 hours.

Print ISSN

0096-6460

Published

1924-05

Content type

Original Research

DOI

10.5594/jj00041