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Essential Components of a High-Speed
Flash Photography System
A complete listing of
all the equipment used for the activities in the Guidebook is given
in Appendix A.
The Camera The more automatic the camera, the less
useful it's likely to be for high-speed photography. Totally manual
cameras are great. That means manual focus, manually-selectable
f-stops, and a B shutter speed setting. (This allows the shutter to
be held open in the dark in readiness for the high-speed event.)
Some of the cameras that I use are the Pentax K1000, the Olympus
OM-1, and the Nikon FM2, but there are many other possibilities.
I've even used a pinhole camera.
Unfortunately, point-and-shoot cameras are generally too automatic
to be used for high-speed photography.
The Film There's nothing special about the film
that you'll need. Many people think that high-speed film is
necessary. I've even seen misleading ads from major photographic
companies implying that by purchasing their fast film, you'll then
be able to take high-speed photographs. I've used films as slow as
ISO 25 and as fast as ISO 3200. It's the flash of light--not the
film and camera--that freezes the action. The advantages of fast
film are i) you don't need as much light to provide a good exposure
and ii) you can use smaller apertures to increase depth-of-field.
The Flash Unit Most inexpensive flash units (sub
$100) can provide a burst of light as short as 1/30,000 second. This
allows you to freeze many high-speed actions or at least to reduce
the blur enough to clearly show the action. The trick is in getting
the unit to give that short of a burst whenever you need it. A flash
unit with automatic exposure is required. The flash unit that I've
found most convenient for high-speed photography is the Vivitar 283.
No, I don't get anything from Vivitar for recommending the use of
this unit. It's just that most flash units are designed for
controlling the flash exposure, not the duration.
Exposure control is great for most photographers, but a high-speed
photographer needs to control the duration of the flash of light.
The 283, more than any other that I've used, makes duration control
easy. It's not that Vivitar intentionally designed the unit that
way. It's just that the modifications necessary to convert the
exposure control circuit to duration control are easier.
The Trigger How do you capture a photograph of,
say, a bursting balloon when it's actually ripping open? You just
have to manage to get the flash unit to discharge at the right time.
It's easy with a sound trigger. A simple one can be made with a
tape recorder and one electronic component. The Guidebook will
describe how to use all the basic trigger types. For
information on constructing your own triggers, see Tools.
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