The high speed cameras that are used at the HITF are Cordin High Speed
Shadowgraph Cameras. They are capable of taking images at a rate of
2.5 million per second. These cameras are quite unlike any conventional
camera. The film is fixed around around a circular housing; at the
center of the circle is a rotating mirror powered by a compressed gas
turbine. There is no shutter; instead, the light source is a pulsed
laser, timed to strike the rotating mirror in such a way that it exposes
one frame of film per pulse. Since the film is stationary, each test
is limited to only 80 frames of film. If you are operating the camera
at 1 million frames per second, that's 80 microseconds of filming.
Fortunately, that's plenty of time, since impacts last only a few microseconds.
Here are some of the more impressive images we have captured using
the Cordin high speed shadowgraph cameras.
Here are some sample Quicktime movies captured using the Cordin high
speed shadowgraph cameras.
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