Bob W <[EMAIL PROTECTED]> wrote: >> Those were photos from Doc Edgerton's lab at MIT. >> They used some good size flash tubes, and >> I believe a microphone was used to trigger the flash. > >> Polaroid film and open the shutter, fire the gun, >> which triggers the flash, and you see where the bullet is. >> Then, adjust the microphone closer or farther away from the gun, >> to get the bullet where you want it in the frame. > >I'm speaking from a position of almost total ignorance here, but >surely a bullet is travelling 2 or 3 times faster than sound? Over the >short distances involved is it really possible to do this?
I don't know anything about the velocity of bullets, but even if they do travel at Mach 3 all you'd have to do is position the target 3 feet from the gun and the microphone 1 foot away and you'd be pretty much synchronized. >I would have thought a light or electric trigger would be better. >e.g. fit the trigger or the hammer of the gun with an electrical gizmo >to fire the flash. A microphone was deemed the easiest way to go: No attachments or modifications to the gun; most equipment readily available off-the shelf. Edgerton claims he got his first shot (the bullet going through the apple, IIRC) on his first try. Clearly, this was a man not unaccustomed to precise laboratory work! -- Mark Roberts Photography and writing www.robertstech.com
