Canon Camera, Hackers Manual

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8.1 Kite Aerial Photography
231
8 Kites, Balloons,
and Multikopters
Despite its name, the Stereo Data Maker is probably most often used for
Kite Aerial Photography ( KAP) and other kinds of remote aerial photogra-
phy. In particular, its excellent support for remote operation, time lapsing,
and the integration of external devices via a serial interface has gained the
SDM a good reputation in the KAP community.
The original version of the CHDK is also used often for remote and unat-
tended operation. In particular, its support for the Lua scripting language
makes it suitable for very sophisticated applications. For example, one of
the weather balloon missions mentioned in the introduction of this book
used a slightly modified version of the original CHDK. A
Lua script handled
the scheduling of both photo and video operations, as well as a shutter-
priority exposure control.
8.1 Kite Aerial Photography
In Kite Aerial Photography (KAP), a camera is lifted by a kite and takes pho-
tographs autonomously or when triggered by a remote control. Small,
lightweight cameras such as the
Canon Digital Elph SD (Ixus) series are ideal
for KAP. Nearly any stable single-line kite design can be used to lift such a
lightweight camera. An interesting option for KAP—although expensive—
is the
Helikite from Allsopp Helikites Ltd., a combination of a helium-filled
balloon and a kite. The advantage of this design is that it can be operated
in both windless and very windy conditions, so you don’t have to rely too
much on the weather—quite important for the professional photographer.
Typically, the camera is mounted on a rig which is suspended some-
what below the kite. By means of gravity, the rig and the camera are kept
aligned with the horizon. There is still some movement, but less than there
would be with a camera directly mounted to a kite. Nevertheless, short
shutter speeds are recommended, and the camera’s
Image Stabilizer (IS)
can also help.
In its simplest form, the camera is mounted directly on the rig in a fixed
position and performs the operations autonomously controlled by a time-
lapse script. The script should allow for an initial delay, so that the kite can
reach its working height before operation starts.