This photo shows the western half of Keppel Henge from about 75 feet up. The photograph was taken using kite aerial photography.
This page of the Keppel Henge website has notes about how to make a simple kite aerial photography rig that can be used to get new perspectives on the landscapes around us.
This photograph was taken at an altitude of about 400 feet. It shows the Analemmatic Sundial and part of the eastern half of Keppel Henge.
Kite aerial photography (KAP) has been used for over a hundred years to get overview perspectives of the landscape. Its advantage over aircraft photography is that much lower altitudes can be used and it is inexpensive. It is also a lot of fun to build a camera rig, try it out and see what you've got! The technique is also used by geologists and archeologists to get plan views of a site.
The basic idea is to suspend a camera with a timer and shutter tripping device below a kite, and send it aloft above the target area. The camera is kept more or less level and properly oriented with an ingenious device called a picavet, which is attached to the kite string.
The kite we use at Keppel Henge is a delta-conyne design with an 7.3 ft wing span and 500 ft of 90 lb test dacron line. This kite design has good lifting ability and is fairly stable once aloft.
A single use camera is used with our rig since it is very light and inexpensive. The rig has to be very robust to take jostling aloft and the crash landings! A dethermalizing timer is used to set a shutter delay of about three minutes long enough to get the rig aloft and in position. The right angle aluminum bar connects to the picavet. This whole assembly weighs about half a pound.
Dethermalizing timers are used by model airplane hobbyists. The one used in our KAP rig is called a Texas DT Timer and is available from Texas Timers. It's a beautifully made mechanism measuring 5 cm in length and weighing just over 18 gm. It holds the shutter tripping bar in place until the set time elapses.
The KAP rig is kept level with a device called a picavet. This has a wooden cross brace that attaches to the KAP rig. About 35 feet of string is threaded through screw eyes located at the end of each brace. The string also passes through a pair of double pulleys that are attached to the kite string, and a single metal key ring located above the braces.
As the kite string's orientation to the ground varies from nearly horizontal to nearly vertical, the picavet string slides through the pulleys and screw eyes, and the KAP rig stays level. The camera has been pointed down at a 45 degree angle at its attachment point with the aluminum bar.
The two double pulleys at the top of the picavet are attached to metal key rings, which are attached to the kite string with a lark's head knot. This type of knot is easy to tie, doesn't slip, and doesn't weaken the string to any great degree. The KAP rig is attached to the kite string about 75 feet below the kite. This makes it easy to launch the kite and the rig is less affected by the kite's random movements.
Why not give kite aerial photography a try yourself?
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