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Cameras
Think of a camera as simply a light-tight box that has a) an
imaging element (lens or pinhole), b) a recording medium (film,
tape, magnetic memory), and c) controls to adjust the exposure of
the medium. We discuss these features as they relate to high-speed
flash photography in this section. The use of conventional film
cameras is covered on this page. The methods described are generally
applicable to the use of digital still and motion video cameras.
Information specific to those cameras is provided from the links to
the left under Cameras.
Using a Conventional Film Camera to
Photograph High-Speed Phenomena
The camera that one uses for high-speed photography need not have
the capability for high shutter speeds, because the duration of the
exposure is determined by the flash rather than the shutter. In
fact, the camera shutter is held open (in the dark) before the flash
discharges. This means that the camera must have either a B (bulb) or
long exposure settings.
The lens should have manual focusing and an adjustable aperture. The
selection of the aperture is determined by the automatic exposure
setting used on the flash. A medium speed film such as ISO 400 is
satisfactory. The higher the film speed, the smaller the lens
aperture can be, thus providing greater depth-of-field. Two suitable and inexpensive cameras that
are no longer being made but can be found used are the
Pentax K-1000 and the Olympus OM-1. These are just two
examples from many. Any SLR camera with the option for full
manual control is fine. Note that point-and-shoot cameras are
generally not usable for high-speed photography, because they
typically don't provide the manual controls described above.
Photographs are usually made in a darkened room. It's a good
idea to have a featureless background to avoid interference with the
subject. However, the background should not be placed too close to
the subject. In the latter case, even a black background can produce
undesirable glare or shadows.
With flash, camera, and trigger positioned as desired, the
shutter of the camera is held open on the B setting in readiness for
the discharge of the flash. After the discharge, the shutter is
released and the room lights turned on.
A few useful accessories are a tripod and a cable release.
Two types of cable releases are shown to the right. The cable
on a spool is an air release. Its 15-foot length make it
especially useful when the photographer must be positioned far from
the camera. Such situations arise frequently in taking
high-speed photographs.
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