A normal motion picture film is played back at 24 frames per second, while television uses 25 frames/s (PAL) or 29.97 frames/s (NTSC). High-speed film cameras can film up to a quarter of a million frames per second by running the film over a rotating prism or mirror instead of using a shutter, thus reducing the need for stopping and starting the film behind a shutter which would tear the film stock at such speeds. Using this technique one second of action can be stretched to more than ten minutes of playback time (super slow motion). High-speed video cameras are widely used for scientific research, military test and evaluation, and industry. Examples of industrial applications are filming a manufacturing line to better tune the machine, or in the car industry filming a crash test to investigate the effect on the crash dummy passengers and the automobile. Today, the digital high-speed camera has replaced the film camera used for Vehicle Impact Testing.