The KAP camera

Choosing a camera for KAP

The right camera for KAP depends entirely on what kind of photos the flier wants from the process. With a little practice good aerial views are possible with almost any camera. Popular choices for KAP fall into 5 types:

  • Mobile 'phone camera.
  • Action camera (GoPro).
  • Compact 'point and shoot'
  • Mirror-less 'large sensor' compacts
  • DSLR
Any camera will work suspended from a kite line provided winds are fair and there is some method of tripping the shutter remotely. The overriding concern is weight. The heavier the camera the more difficult it is to fly!
To begin with it is sensible to practice with a cheap camera as this is when mistakes are made and the loss of a precious camera is best avoided while gaining confidence in lifting weights by kite. For a modest outlay it is possible to get a good idea of how the world looks from above and the kind of capture possible.

KAP photos are taken much further away from the subject than is usual for photographers working on the ground. The kind of distances involved are more usual in landscape and air survey photography. By replacing the tripod with a kite the benefit of long exposures or long focal lengths is lost: a kite suspended camera is always subject to movement. To achieve good resolution the KAP camera is a compromise between weight and resolving power.

In the era before reliable aircraft George Lawrence used a 49lb panoramic camera lifted by a train of up to 19 man sized delta Conye kites. Modern digital cameras weigh a great deal less!

photo courtesy of the Lawrence Family

Remote control of the shutter and changing the negative required returning the camera to the ground after each shot. Sir Henry Wellcome devised a vane driven traveler system to recover the camera after exposing the plate to record the archeological excavation of  Jabel Moya, Sudan in 1913.

photo copyright Welcome Foundation

Using the GoPro

At only 70g heavy the minature wearable HD 'action' camera has great potential to get in the sky, even in the lightest winds. Simple rigs to suspend it can be fashioned easily and it has an impressive array of mounting options that can be modified for KAP. Go Pro images are characteristically fish eyed and this is perhaps their biggest limitation: when the spherical projection is corrected only a small central area is distortion free.

The only exposure setting you have is 'Spot Meter' on or off (default).

Photo Resolution (FoV) is purely dependent on personal preference, though most people tend to shoot wide angle (default) to utilize the "entire" sensor.

Photo Burst or Continuous Photo can only be useful if you trigger the camera using an external device, such as gentWIRE-HERO

Time Lapse is how I use my GoPro when I KAP. I set it to take a picture once every 5 seconds. You may change the intervals to 0.5, 1, 2, 5, 10, 30 or 60 seconds.

The "One Button" mode can be extremely useful. When selected, the camera automatically begins recording as soon as you power on the camera.

"Default" mode as well as "Upside Down" can also be very useful for KAP.

The Sound & Light Status indicators can be switched off to extend battery life but are very useful to ensure the camera is taking pictures before sending the camera up in the air.

Refer to the GoProproduct manuals for more details.

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The light weight advantage of the 'action' camaera  is such that a multiple camaera set can be used for panoramic capture:














photo: Gentles Ltd


Which compact?

Compacts are available in a wide variety including ruggedised versions. They are characterized by a small sensor and short focal length. 

A camera which has manual control of the exposure is better than one without as setting the ISO and shutter speed is important.

A tripod screw hole is an important feature as it allows the camera to be fitted securely to a rig, some are plastic and can wear out quickly. 

Many feature image stabilisation which is desirable.

There is much to be said for selecting a camera which can be tripped by intervalometer or time lapse so check if  this feature is available. Many Canon compact cameras can be operated by substitute firmware (CHDK) and compatibility of a given camera a can be checked on the: CHDK wiki

Robust, light weight and controllable by CHDK. The Canon Ixus/Elph is a firm KAP favorite.

Some 'high end' compacts feature accessory mounting points for a lens tube and a hot shoe.  A hot-shoe is a good fitting point for a shutter servo and a lens tube can be used for a wide angle adaptor or filters and lens hood.


Which mirrorless?

Larger format than compact and smaller than a DSLR the 'mirrorless compact' offers the photographer better resolution than the compact and, on some models, a choice of lens. The large sensor enables these cameras to function with high speed sensitivity settings (ISO) which is useful.  The weight saving over a DSLR is significant. Fixed lens models are lighter than ones with swappable lenses. Many models are 'professional 2nd camera' quality devices with metal casing, good for robustness but heavier.

Not all compact mirrorless designs are fitted for IR shutter release and many use HDMI video output which is more difficult to relay to ground than the analogue 'AV out' option.

Mirrorless Micro 4/3rds camera fitted with hot-shoe mounted shutter servo for remote control.

A popular APSC format choice for KAP, as it has its own intervalometer (so can be used for autoKAP without modification for remote shutter release) and weighs only 245g, is the Ricoh GR:



DSLR KAP
The weight of the DSLR camera requires the use of bigger (3m2+) kites, heavier line and more down wind space than a compact. The benefit of committing a high quality lens and sensor to the skies is the increased resolution possible. The lightest bodies are around 500g and, with a lens, 1.5kg is common. Live view can be used for video relay although power consumption in LV mode is high.


photo Tom Benedict

A heavy camera means balance on the rig is important to prevent damage to servos.

Many of the advantages of the smaller DSLR cameras are overlapped by the compact mirrorless models, often  using the same sensor in both formats. The DSLR retains the advantage of fast AF and a wide range of optimized lens designs.

How do I trip the shutter?

The camera will need a method of tripping the shutter whilst its in the air and there are 3 common methods of achieving this:

  • Intervalometer or 'time lapse' feature
  • Infra Red (IR) remote
  • Radio control

see also: KAP Electronics

What settings should I use?

ISO. Sharp shots are more likely to be achieved with a fast shutter speed. One method of ensuring this is to fix the sensor sensitivity. In program mode (P) the ISO can be set at a high value: 800 is a good starting point.

Exposure Value (EV). It is common for objects on the ground to appear much brighter than they are on the ground. It can be useful to set the EV to -2/3rd to accommodate this.  

Fixed focus. If the camera is to be high in the sky there can be merit in turning off AF and fixing the focus to infinity. Some AF responses are very slow if the camera is swinging to and fro, sometimes to the point where the shutter won't fire. Fixing the focus and taping the lens to stop it drifting is a good idea if this is the case.

Polarising Filter. A camera in the sky is prone to glare effects. A PL filter helps.

RAW image format is useful to get the most out of post processing images, settling for JPEG may be a good option if image stabilisation is not available for RAW.

The biggest killer for KAP photos is motion blur. Even the best of kites, nailed to the sky, will move around. I wind up using shutter priority mode  most of the time I'm doing KAP. A shutter speed of 1/640 or faster results in a really good sharp/blurry ratio.

photo N-blueion

One tip from Brooks Lefler is to under-expose by 1/3 to 2/3 stops. When you've got a camera on the ground, reflections off of shiny stuff like plant leaves and grass are a pain, but it doesn't dominate the frame. When the camera is in the air and the sun is at your back, more of the reflections point straight back at the camera, so the scene can come out looking brighter. Once a bright spot exceeds the max value of a pixel (255 for a JPG), you can't get that information back. It's blown. By under-exposing, you wind up with darker images that can later be tweaked in editing. But the highlights stand a better chance of not being blown. (A side-benefit of this is that under-exposing makes for shorter exposure times. Bonus!)

I tried different white balance settings. Sunsets, in particular, wash out if auto white balance mode is used. I found a way to bump the sunset color palette was to either leave the camera set on daylight WB, or set it to cloudy to give everything a warmer cast.

Tom Benedict

Lens choice for low level aerial photography

It is perhaps surprising that the limited height for many KAP flights means a wide angle lens is of benefit. A handful of compact cameras have wide angle adapters available. 

KAP Panoramas are one way of getting wider cover and shooting with a rig set up for this enables the use of 'standard' prime lenses for wide cover. Fisheye lens capture does not lend itself to panoramic stitching, even when perspective corrected fitting is very difficult.

'Pancake' lenses have the benefit of a wide view in a lightweight package with manageable distortion.

The fixed lens design of many compact cameras is an advantage in terms of weight and the 'standard' field of view of a focal length of 50mm (35mm frame equivalent) will give excellent results.

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