Time delayed still shots using a sound activated flash.
   Starting with the sound trigger used in an article entitled "High Speed Flash Photography with Sound Triggers" from the January 1990 issue of The Physics Teacher we've been able to investigate a variety of things.  The quality of the pictures may not be all that great when film was not used but they were much more cheaply and quickly obtained.  If you're not into delayed gratification this is great.  These pictures were all taken using the delay in time caused by the distance between the source of the sound and the microphone that triggers the flash.  Since sound travels at 1100ft/s this means that every foot of separation is about 1millisecond time difference.  The flash is either a cheap recyled camera or a regular flash attachment, either works fine for our purposes, and the microphone is a tape recorder, not just a tape player,  with a headphone jack.  Most recorders seem to work well but some will not produce enough signal at the headphones when in the record mode and some will produce too much.  You can either try different recorders till you find one that works or use a variable resistor to adjust sensitivity.
   We, one of our engineering students and I, are currently working on what we hope is a relatively cheap, more general purpose trigger and I hope she'll be able to present her results later this semester.
    Some high speed pictures were taken in 3D as well and can be seen on the 3D Page.  This technique works especially well with glow in the dark screens to take shadow images quickly.  These don't photograph well so if you want to see some please drop by and see me about it.

Frame by frame with a videocamera
   Another way to get pictures of things as they happen is to use a standard videocamera.  When played back frame by frame on a VCR you get one picture every 1/30 of a second.  This is actually quite a big gap in time for something that happens very rapidly but if you take enough pictures sooner or later you'll catch even very brief events.  It is important for most purposes to be able to put the camera on as rapid a shutter setting as possible.  This means you'll need as much light as possible because in effect what the camera does is take a very quick exposure every 1/30 of a second so the picutres appear dimmer and dimmer as the shutter setting becomes shorter.  We've had best luck outdoors on a sunny day.  Water balloons are especially fun to look at.  Here's one that believe it or not didn't pop even after this!  (More to come.)