This device translates the ground speed of an aircraft into the proper time interval between pictures. This is done by adjusting the speed of a movable bar to follow the speed of ground objects as they cross the view finder field. Connected to a K-3A camera by cables, the finder automatically trips the shutter when the correct area has been covered and then repeats for the next field of view.
Transferred from the U.S. Navy
12-3/4in. long; has 8-1/2in. ef , F.45 lens; automatic interval finder, viewer. Has lined case, 2 power cords. Bausch & Lomb lens.