Kite aerial photography
Encyclopedia
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 photograph
s. The camera rigs can range from the extremely simple, consisting of a trigger mechanism with a disposable camera, to complex apparatus using radio control and digital cameras. On some occasions it can be a good alternative to other forms of aerial photography.
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
. Cameras using internal image stabilization
features can increase the number of sharp photos. In order to take photographs that are oriented correctly with the horizon, a suspension method is used to allow the rig to automatically level itself under the kite line.
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.
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 wired connection to instruct the camera to release the shutter, or by 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 within a frame, this '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 by 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.
designs. Almost any stable kite design can be used to lift lightweight camera rigs (up to approx 500g/1lb). As weight increases, specific designs are chosen for their additional flying characteristics, such as line pull, wind range, flying angle and ease of launch. Widely used designs are parafoil
, rokkaku, delta (including variations such as delta conyne) and the new lighter-than-air helikite
design. Of these, the parafoil is most popular as it generates a strong pull for its size, and can be easily stored in a small space due to its sparless construction. Sparred kites such as the rokkaku or delta tend to fly at a higher angle than parafoils, which is of benefit when the space between the launch site and photographic subject is limited. A higher flying angle permits the kite to lift more weight, as more of the generated force is acting vertically. Helikites allow reliable KAP in difficult conditions, thus opening up the use of KAP for professional photography.
The first kite aerial photographs were taken by British meteorologist Douglas Archibald in 1887 and Arthur Batut
in Labruguière (France) in 1888.
Manned kite flying and aerial photography was advanced also by French Marcel Maillot, British Robert Baden-Powell, Americans Charles Lamson and William Abner Eddy
, Australian Lawrence Hargrave
(inventor of box kite
in 1893 and kite train in 1884) and French Captain Saconney
.
The famous kite image of San Francisco
after the 1906 earthquake
(right) was taken by an early pioneer in KAP, George Lawrence using a large panoramic
camera and stabilizing rig he designed.
Practical and commercial use of KAP is limited by the unpredictability of the weather (notably wind, sun and rain) and the fact that not every site is suitable to flying a kite. Launching a kite near buildings or downwind of trees can be problematic, due to heavy turbulence.
The main applications today are amateur photography, art and archaeology. Attempts to commercialise KAP have so far been largely unsuccessful.
Hobby
A hobby is a regular activity or interest that is undertaken for pleasure, typically done during one's leisure time.- Etymology :A hobby horse is a wooden or wickerwork toy made to be ridden just like a real horse...
and a type of photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
. A camera is lifted using a kite and is triggered either remotely or automatically to take aerial photograph
Aerial photography
Aerial photography is the taking of photographs of the ground from an elevated position. The term usually refers to images in which the camera is not supported by a ground-based structure. Cameras may be hand held or mounted, and photographs may be taken by a photographer, triggered remotely or...
s. The camera rigs can range from the extremely simple, consisting of a trigger mechanism with a disposable camera, to complex apparatus using radio control and digital cameras. On some occasions it can be a good alternative to other forms of aerial photography.
Camera rig and stabilisation
Shutter speed
In photography, shutter speed is a common term used to discuss exposure time, the effective length of time a camera's shutter is open....
to reduce motion blur
Motion blur
Motion blur is the apparent streaking of rapidly moving objects in a still image or a sequence of images such as a movie or animation. It results when the image being recorded changes during the recording of a single frame, either due to rapid movement or long exposure.- Photography :When a camera...
. Cameras using internal image stabilization
Image stabilization
Image stabilization is a family of techniques used to reduce blurring associated with the motion of a camera during exposure. Specifically, it compensates for pan and tilt of a camera or other imaging device. It is used in image-stabilized binoculars, still and video cameras, and astronomical...
features can increase the number of sharp photos. In order to take photographs that are oriented correctly with the horizon, a suspension method is used to allow the rig to automatically level itself under the kite line.
Pendulum suspension
Oscillation
Oscillation is the repetitive variation, typically in time, of some measure about a central value or between two or more different states. Familiar examples include a swinging pendulum and AC power. The term vibration is sometimes used more narrowly to mean a mechanical oscillation but sometimes...
due to movement from the kite line and wind pressure, but the camera will remain steadier and more level than without a pendulum.
Picavet suspension
A Picavet suspension, named after its French 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 settle naturally into a level position. The dimensions and shape of the Picavet have been adapted many times in attempts to increase stability or to improve portability.Shutter release and camera positioning
The shutterShutter (photography)
In photography, a shutter is a device that allows light to pass for a determined period of time, for the purpose of exposing photographic film or a light-sensitive electronic sensor to light to capture a permanent image of a scene...
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
Servomechanism
thumb|right|200px|Industrial servomotorThe grey/green cylinder is the [[Brush |brush-type]] [[DC motor]]. The black section at the bottom contains the [[Epicyclic gearing|planetary]] [[Reduction drive|reduction gear]], and the black object on top of the motor is the optical [[rotary encoder]] for...
to press the shutter release button, using an infrared signal or wired connection to instruct the camera to release the shutter, or by using the camera's inbuilt intervalometer
Intervalometer
An intervalometer is a device which counts intervals of time. . Such devices commonly are used to signal, in accurate time intervals, the operation of some other device...
. 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 within a frame, this '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 by 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
Radio control
Radio control is the use of radio signals to remotely control a device. The term is used frequently to refer to the control of model vehicles from a hand-held radio transmitter...
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.
Kites
The most important aspect of any kite used to lift a camera is stability. Generally single lined kites are used as they allow very long line lengths and need less intervention from the flyer than steerableSport kite
A sport kite, also commonly known as a stunt kite, is a kite that can be maneuvred in the air.A related kit also controllable and used for recreation, but capable of generating a significant amount of pull and used for providing movement is the Power kite.-Competition:Developments in multi-line...
designs. Almost any stable kite design can be used to lift lightweight camera rigs (up to approx 500g/1lb). As weight increases, specific designs are chosen for their additional flying characteristics, such as line pull, wind range, flying angle and ease of launch. Widely used designs are parafoil
Foil kite
Foil kites are soft kites based on the design of the parafoil. They consist of a number of cells running fore to aft, some or all of which are open at the front to allow air to inflate the kite so it takes on an aerofoil section...
, rokkaku, delta (including variations such as delta conyne) and the new lighter-than-air helikite
Helikite
The names Helikite and Helikites, are Allsopp's Registered Trade Marks relating to a new type of kite-style aerostat designed and patented by Sandy Allsopp in England....
design. Of these, the parafoil is most popular as it generates a strong pull for its size, and can be easily stored in a small space due to its sparless construction. Sparred kites such as the rokkaku or delta tend to fly at a higher angle than parafoils, which is of benefit when the space between the launch site and photographic subject is limited. A higher flying angle permits the kite to lift more weight, as more of the generated force is acting vertically. Helikites allow reliable KAP in difficult conditions, thus opening up the use of KAP for professional photography.
History
Arthur Batut
Arthur Batut was a French photographer and pioneer of aerial photography.-Life:Batut, born 1846 in Castres, was interested in history, archeology and photography...
in Labruguière (France) in 1888.
Manned kite flying and aerial photography was advanced also by French Marcel Maillot, British Robert Baden-Powell, Americans Charles Lamson and William Abner Eddy
William Abner Eddy
William Abner Eddy was an American accountant and journalist famous for his photographic and meteorological experiments with kites....
, Australian Lawrence Hargrave
Lawrence Hargrave
Lawrence Hargrave was an engineer, explorer, astronomer, inventor and aeronautical pioneer.- Early life :Hargrave was born in Greenwich, England, the second son of John Fletcher Hargrave and was educated at Queen Elizabeth's Grammar School, Kirkby Lonsdale, Westmorland...
(inventor of box kite
Box kite
A box kite is a high-performance kite, noted for developing relatively high lift; it is a type within the family of cellular kites. The typical design has four parallel struts. The box is made rigid with diagonal crossed struts. There are two sails, or ribbons, whose width is about a quarter of the...
in 1893 and kite train in 1884) and French Captain Saconney
Jacques Theodore Saconney
Jacques Theodore Saconney was a Senior French Army General, an innovative scientific and an adventurous balloonist....
.
The famous kite image of San Francisco
San Francisco, California
San Francisco , officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of 7.15 million people which includes San Jose and Oakland...
after the 1906 earthquake
1906 San Francisco earthquake
The San Francisco earthquake of 1906 was a major earthquake that struck San Francisco, California, and the coast of Northern California at 5:12 a.m. on Wednesday, April 18, 1906. The most widely accepted estimate for the magnitude of the earthquake is a moment magnitude of 7.9; however, other...
(right) was taken by an early pioneer in KAP, George Lawrence using a large panoramic
Panoramic photography
Panoramic photography is a technique of photography, using specialized equipment or software, that captures images with elongated fields of view. It is sometimes known as wide format photography. The term has also been applied to a photograph that is cropped to a relatively wide aspect ratio...
camera and stabilizing rig he designed.
KAP today
With the advent of the internet, light and affordable digital cameras, radio control and microelectronics, kite aerial photography has become increasingly popular. In latter years, kits have become available that enable a beginner to quickly assemble a functional KAP rig and start taking aerial pictures in the visible part of the spectrum and, with more experience, in the near ultra-violet, near and thermal infra-red parts of the spectrum too.Practical and commercial use of KAP is limited by the unpredictability of the weather (notably wind, sun and rain) and the fact that not every site is suitable to flying a kite. Launching a kite near buildings or downwind of trees can be problematic, due to heavy turbulence.
The main applications today are amateur photography, art and archaeology. Attempts to commercialise KAP have so far been largely unsuccessful.
External links
- Kite Aerial Photography Information
- Kite Aerial Photography Forum
- KAP jargon explained
- George Lawrence and information on his photographs of San Francisco
- Sample Kite Aerial Photographs
- Photographs of Kite Aerial Photography Rigs
- HD-Kite-Panoramic Photos
- Kite Aerial Photographers - Archaeology