The Aerial Camera

Aerial cameras have evolved significantly over the past 75 years. Today's aerial camera is a sophisticated instrument capable of producing amazingly sharp high definition photographs.

The camera uses rolls of film 9 inches wide by 200 to 400 feet in length. Each negative is 9" x 9". Our camera is fitted with a 6 inch Zeiss lens and the camera is calibrated by the United States Geological Survey. (see our camera calibration)

The film is held flat during exposure by a vacuum pump and to compensate for the movement of the aircraft, the film carriage moves slightly forward during exposure (forward motion compensation). For mapping applications, the camera exposure is connected to a GPS receiver to record the location of each exposure. An IMU (inertial measurement unit) is used to record the attitude of the aircraft.

We fly our photography on long flight lines at a pre-determined altitude. As we fly along the flight line, we make our exposures so that each photograph overlaps the preceding photograph by about 60%. Along adjoining flight lines, each photo overlaps the photo on the next flight line by about 30%. As a result, this photography can be viewed stereoscopically using the proper equipment.

Our archival photography is capable of producing topographic maps, or up to 50x enlargements.

The photography is flown as vertical (straight down) or oblique (angled). The vertical photography is at various photo scales, but primarily at 1:12,000 (one inch on the negative equals 1000 feet on the ground).