The high speed cameras that are used at the HVIT 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.