Jan 21, 2009: Digital Weird

[Scriveyn]

There are classic (non-digital) SLR cameras which have a slit moving across the film (focal plane shutter) rather than a central shutter. I dimly remember reading about strange effects that can be produced by these, so I looked it up on wikipedia (see quote below). - So this not an effect new or restricted to digi-cams.

Originally Posted by from wikipedia

Distortion of fast-moving objects: although no part of the film is exposed for longer than the time set on the dial, one edge of the film is exposed an appreciable time after the other, so that a horizontally moving shutter will, for example, elongate or shorten the image of a car speeding in the same or the opposite direction to the shutter movement. For an example of such distortions see this image taken with a vertically traveling focal-plane shutter, showing extreme distortion of fast-moving helicopter rotor blades.