Camera obscuras were used for training and bombing practice in both World War I and World War II.

The 6 1/2" X 8 1/2" glossy photograph below is stamped "Sep 15 1918" and "Committee on Public Information". It shows the interior of a portable camera obscura used for aviation training or bombing practice in World War I. In use the turned back covere would be lowered to render the interior dark. As the projected image of an airplane moved across the table its path could be traced and its speed could be measured with the metronome seen on a shelf on the left side of the tent.

We have seen this image printed in publications of the time with a caption stating that the tent was for use "ON" planes. This seems obviously wrong since the lens is overhead and it would project an image of the sky down onto the table which would be useless.

The photograph in the next row below, labeled as "Hamilton Field, California" and dated "9/16/35" shows changes in the use of the camera obscura in military aviation between 1918 and 1935.

The body of the camera obscura is now a metal capsule with a lens mounted on the top. The metronome has been replaced with a rack of electronic equipment connected to the camera obscura. In a close up we see though an open window, a young man wearing head phones with a pencil poised over a drawing board that is tilted at the same angle as the lens.

In the background are several 1930 era airplanes.