Re: videotape data on free fall

[Leigh Palmer <palmer@sfu.ca>]

> In some cameras the way in which fast shutter speeds are attained is by
> sweeping a slit across the face of the film.  The film is only exposed
> when the slit is in front of it.  Thin, fast moving slits make for short
> exposures.  Is this how a cam corder works?  Is this relevent to producing
> "clean" images of fast moving objects?  Does the orientation of the camera
> matter?

I don't think so. The focal plane shutter produces distorted photographs.
The old Speed Graphic pictures of Indianapolis champions taking the
checkered flag in their elliptical-wheeled cars is a good example, one
which penetrated the culture to the extent that elliptical wheels were
drawn in cartoons to indicate speed*. My camcorder produces no such
distortion when used at high "shutter speeds", but as I said before, it
might be the case that not all camcorders work that way.

Leigh

*Another interesting device is the stationary slit and moving film camera
that is used to photograph the finish line in horse and human races.