Flash duration is about 1/10000 sec. I would think a bullet from a gun that has just been fired. Use a wire to hold the flash off so it triggers as the bullet breaks the wire. The circuit would be a transistor going to ON to fire the flash and an transistor I the inverting amplifier configuration holding the flash fire transistor off until the wire is cut. The muzzle velocity of you gun should be available from the gun smith and so the length of the blur will enable you to compute the duration of the flash. Warning! Guns are dangerous so don't shoot yourself or anyone else during the measurement. You will need a couple of sandbags to safely stop the round. Chris -----Original Message----- From: owner-photoforum@xxxxxxxxxxxxxxxxxx [mailto:owner-photoforum@xxxxxxxxxxxxxxxxxx] On Behalf Of Herschel Mair Sent: 28 January 2011 05:07 To: List for Photo/Imaging Educators - Professionals - Students Subject: flash duration Andy, something right up your alley! I want to measure flash duration of an old dynalite head and pack. What can I shoot in the dark that moves at a constant speed and is really cheap? Or can anyone suggest a set up. Herschel
