Freezing Time with High-Speed Photography

By Earl Hunsinger

Does a galloping horse ever take all four feet off the ground at the same time? That was the question asked in 1872 by former California governor and racehorse owner Leland Stanford. The man he asked was a successful landscape photographer by the name of Eadweard Muybridge. To answer the question, Muybridge turned to high speed photography.

As the Rochester Institute of Technology’s A BRIEF HISTORY OF HIGH SPEED PHOTOGRAPHY 1851-1930 explains, other photographers had begun experimenting with high speed techniques as early as 1851. Yet the work done by Muybridge is perhaps the most famous. The webpage for the Long Island University course Instrumented Analysis of Human Movement contains the original photographs taken by Muybridge. These clearly show that a horse does lift all four feet off the ground while running. The series of photographs, called "Galloping Horse" or "The Horse in Motion" were taken in 1878, six years after the question was first posed.

As the article Lights, Camera, Eureka! explains, Muybridge first tried to use a series of cameras set in a row with trip wires activated by the horse as it galloped past. This was ineffective for two reasons. The shutters opened too slowly, causing a picture to be taken after the horse had passed, and they closed too slowly, allowing in too much light and thus blurring the pictures that resulted. To solve the problem, he devised a method using electricity and magnets, which would allow the shutters to open and close more quickly.

For modern high speed photographers, the problem remains the same, how to get the shutter to open and close fast enough to capture a clear image of the instant in time that you desire. As explained on a High Speed Photography webpage from the Astrophysics Research Institute of the Liverpool John Moores University, there are a couple of approaches to solving this problem. You can either use a faster shutter or a faster light.

Since the shortest shutter speed of a typical single lens reflex camera is about 1/1000 of a second, with dual wipe shutter blades that take longer than that to travel across the shutter window, it is difficult for an amateur to take high speed photographs by using the faster shutter method. The use of a faster light is a better solution.

A single lens reflex camera allows you to leave the shutter open while the button is held down. Of course, under normal lighting conditions exposing the film in this way would not achieve the desired result. This is where a fast light comes into play. The subject is held in complete darkness, with the only light supplied by a simple flash gun set to automatically provide illumination for a short duration. Such flash guns can be purchased with a flash duration of 30 microseconds or less. Of course, lighting the subject with a flash of light is only half the battle. If you don’t turn on the light at the proper time, you don’t get a very impressive picture. The above website also discusses some ways to automatically fire your flash gun.

The art and science of photography has come a long way since the days when Muybridge tried to prove that a horse lifted all four legs at once. Research institutions like the Science and Technical Research Laboratories of Japan’s NHK are developing cameras capable of capturing up to a million frames per second. Yet for the amateur, high speed photography is still a fascinating and accessible hobby.