In May of 1973, the Boller and Chivens division of the Perkin Elmer Corporation purchased the Microdensitometer product line from Photometric Data Systems Corporation.
The instruments produced were numbered in the 30’s.
One application was that all photos transmitted from space could be scanned and converted into images where colors and densities could be altered for better identification.
This ability became very useful in a number of different types of applications. Eastman Kodak was a major purchaser of these instruments.

For more information about Microdensitometers, visit: http://www.astro.virginia.edu/~rjp0i/museum/PDSMicro.html