How high-speed photographs are taken?

To freeze the beating of an insect’s wing needs a far shorter exposure than an ordinary camera can manage. Even at 1/1000th of a second the wings are a blur. Exposures ten or twenty times shorter are needed.

The British photographic pioneer W.H. Fox Talbot also pioneered high-speed photography as long ago as 1851. He attached a copy of The Times newspaper to a wheel, rotated it rapidly, and succeeded in taking a clear picture by illuminating the wheel very briefly with an intense spark of light which lasted only 1/100,000 of a second. If this technique is used in a blacked-out room, the camera shutter can be left open, and the film is exposed for an instant when the spark goes off.

The greatest difficulty is to arrange for the flash to go off when the subject is in exactly the right position. Often the best way is to make the subject – such as a bullet speeding through an apple – trigger the shutter or flash (or both) itself, by breaking a fine infrared beam or light beam that is focused on a reactive cell, for example.

A series of flashes may be used, with the film moving between each one. This technique was pioneered by an American, Harold Edgerton, in the 1930s. By using ten flashes a second and superimposing all the images on the same frame, he was able to show a drop of milk splashing into a bowl.


Picture Credit : Google