High Speed Photography by Alan Sailer

These amazing high speed photographs are the work of Alan Sailer, who is based in California, USA.

A normal photographic flash unit gives a flash that lasts around a thousandth of a second (a millisecond). However Alan's flash unit is much faster than this, and produces a flash of light around a microsecond (a millionth of a second). This allows him to freeze things that are happening extremely fast, and to give us a view of something that otherwise we would never see.

The other key part of Alan's set up is an automatic trigger mechanism, as the pellet passes through a laser beam. When this happens, the flash is triggered. However in order to be able to fine tune the image, there is an adjustable delay circuit, so the flash will trigger at a precise moment after the pellet has passed through the laser beam. The digital camera (a Nikon 40X) uses a fairly slow shutter speed. The photograph is taken in darkness, and while the camera shutter is open, the high speed flash captures the image. Alan says that this allows him to catch the pellet is space with an accuracy of a few millimetres.