Canon Camera, Hackers Manual

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C H A P T E R 5 Scripting
entire specified area of sharpness. This is particularly true for macro and
telephoto work. Make sure you have enough space on your memory card
and use fully loaded batteries.
5.7.3 Motion detection
Motion detection is one of the great features of the CHDK. This feature
makes use of the camera’s hardware motion detection facilities. The cam-
era provides such facilities for its own purposes: to enable image stabiliza-
tion and to adjust exposure time in regard to subject movements. The
CHDK uses them to trigger events—in most cases, to fire a shot. But if you
like, you can play a sound instead. CHDK motion detection has many useful
applications, such as lightning photography, wildlife and sports, surveil-
lance, and more.
Basics
Motion detection is enabled by the CHDK command md_detect_motion .
uBasic:
md_detect_motion a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p
Lua:
h = md_detect_motion(a, b, c, d, e, f, g, nil, i, j, k, l, m, n,
o, p)
Figure 5-4
Breuburg Castle, Germany. A picture
like this cannot be obtained in a single
shot with a camera that has an ND
filter but no diaphragm. The Adaptive
Focus Stacking script was used to shoot
a series of differently focused images.
The settings a=45, b=1, d=3 resulted in
a focal range of 45 cm to infinity. The
six shots were then composed in
CombineZP . Some retouching was
required for the clouds that were
moving fast between the shots,
resulting in a staggered effect.