With high speed photography, I can use a high voltage spark to
create a flash of only 1/1,000,000th of a second in duration.
The problem is that there are not a lot of things that move this
fast that such a flash is required to stop the motion. Bullets
are such a subject requiring a very high speed flash system.
Around the lab we jokingly call this “ludicrous speed”. After
photographing bullets hit just about every conceivable object it
is time to move on to other subjects. In this case a paint ball
is sent into the edge of a straight razor blade. The paint ball
crosses two optical detectors that measure the velocity (166
feet per second) then trigger the flash when the paint ball has
traveled about 12 inches. The momentum of the paint ball keeps
the ball in motion even after being sliced in half by the razor
blade. A wonderful way to illustrate Newton’s Law of Inertia –
that is, an object in motion will stay in motion until a
suitable force is applied to stop it. With many photo sessions
once the photography