This section is from the book "Aerial Cameras, Aerial Films, And Film Processing", by Richard W. Underwood.
The modern aerial camera took on its basic design before the advent of practical and economical utilization of color Rims. It was not necessary then to manufacture lenses with polychromatic capability. A yellow filter was usually incorporated into the optical system to subdue the response to near ultraviolet and blue light, which is usually present due to suspended aerosols and other particulate matter found in the atmosphere.
In the past few years it has become economically feasible to use aerial color films. The beautiful color photographs of the Earth secured by Gemini astronauts made this fact dramatically clear. If your Earth survey plans call for the use of aerial color films, it is absolutely necessary that you use a polychromatic (color-corrected) lens in your aerial camera.