Kite aerial photography

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Early kite photo from 1906

Kite aerial photography (KAP) is a hobby and a type of photography. A camera is lifted using a kite and is triggered either remotely or automatically to take aerial photographs. The camera rigs can range from the extremely simple, consisting of a trigger mechanism with a disposable camera, to complex apparatuses using radio control and digital cameras. On some occasions it can be a good alternative to other forms of aerial photography.

1 Camera rig and stabilisation
- 1.1 Pendulum suspension
- 1.2 Picavet suspension
2 Shutter release and camera positioning
3 History
4 See also
5 External links

[edit] Camera rig and stabilisation

The camera can be attached directly to the kite but is usually secured to an adjustable rig suspended from the kite line at a distance from the kite. This distance reduces excessive movement being transmitted from the kite to the camera and allows the kite to be flown into higher, stable air before the camera is attached. If possible, the camera is set to a high shutter speed to reduce motion blur. In order to take photographs that are orientated correctly to the horizon, a suspension method is used to allow the rig to automatically level itself under the kite line.

[edit] Pendulum suspension

This simple levelling method involves suspending the camera from a rigid length of material below the kite line. Gravity naturally keeps the rig level, irrespective of the angle of the kite line. The pendulum will oscillate due to movement from the kite line and wind pressure, but the camera will remain steadier and more level than without a pendulum.

[edit] Picavet suspension

A Picavet suspension, named after its inventor Pierre Picavet, consists of a rigid cross suspended below the kite line from two points. A single line is threaded several times between the points of the cross and the points of attachment to the kite line and the rig is attached to the cross. The Picavet line runs through eye hooks or small pulleys so that the weight of the rig causes it to naturally settle in a level position. The dimensions and shape of the Picavet have been adapted many times in attempts to increase stability or to improve portability.

[edit] Shutter release and camera positioning

The shutter of the camera can be released in several ways, depending on the type of camera and complexity of the rig electronics, if used. Shutter release mechanisms include using a radio controlled servo to press the shutter release button, using an infrared signal or using the camera's inbuilt intervalometer. Ideally the camera is allowed to reach its final altitude before the shutter is released to avoid taking photos during launch.

Fixing the camera directly to the kite or line makes changes to positioning awkward. If the camera is fitted in a rig, the rig can be designed to rotate horizontally and vertically and to change the picture format from portrait to landscape by rotating the camera. Adjustments to these angles can be made be manually setting the rig on the ground or by adjusting the rig while it is airborne using a remote control or an automatic controller in the rig. Commonly a radio control system, as used for model aircraft is used. The servos in these systems are readily adaptable to adjust rig positioning. Several automatic controllers have been developed that can take a photo, move the camera by a set angle, take the next photo and so on.

[edit] History

The first kite aerial photograph was taken by Arthur Batut in Labruguière (France) in 1888.^{[citation needed]}

The example image of San Francisco after the 1906 San Francisco earthquake was taken by an early pioneer in KAP, George Lawrence using a large panoramic camera and stabilizing rig he designed.