Abstract

An f : 2 photographic lens having five separated elements was treated with evaporated fluorite to decrease the reflection from all ten air-glass surfaces. Photographs were taken with the lens under carefully controlled conditions before and after it was treated. The effective speed of the lens was found to be almost doubled by the treatment. A slight increase in contrast resulted in photographs taken under normal lighting conditions and a large increase in contrast resulted in those taken under adverse lighting conditions. An increase in detail was observed, because of the absence of flare, and the ghost images usually observed under adverse lighting conditions were eliminated.

© 1940 Optical Society of America

Some Observations on Low Reflection Evaporated Fluoride Coatings

George S. Monk
J. Opt. Soc. Am. 30(11) 571-572 (1940)

An Intensity-Scale Monochromatic Sensitometer*

Charles H. Evans
J. Opt. Soc. Am. 30(3) 118-127 (1940)

Investigation of Thin Evaporated Silver Films on Glass

John Strong and Barry Dibble
J. Opt. Soc. Am. 30(9) 431-438 (1940)

Experiments to Test the Rebromination Theory of Photographic Solarization*

J. H. Webb and C. H. Evans
J. Opt. Soc. Am. 30(9) 445-454 (1940)

A Multipurpose Photoelectric Reflectometer

Richard S. Hunter
J. Opt. Soc. Am. 30(11) 536-559 (1940)