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Old 22nd October 2013, 02:35 PM
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RobF RobF is offline
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Originally Posted by Monty View Post
I've tried this myself but failed! I need to sort out a sound activator for the release on a pair of Nikon SB800 speedlights. Problem with using a camera shutter to freeze movement is that even on my D3 I'm limited to 1/8000th which just isn't fast enough, Neil- the pellet may be in shot but it's moved to far during the exposure to register an image on the sensor. If you use decent off body flash unts on manual rather than TTL at their lowest power setting you can get 1/64000 second exposure but you need to shoot in darkness with the shutter open for a few seconds and let the flash do all of the work. Generally the body and flash don't sync at anything much over 1/250th so you need to do a multi second exposure on the body with a fast lens and let the flash determine the exposure time. No point using studio heads, even my fast ones are limited to 1/3200 of a second, it has to be speedlights.

Anyone seen a device that closes a circuit that's sound activated? All the light need to fire is for something to close the circuit between the inner and outer contacts on the co-ax connection. I'd be interested in trying this out again!

Monty. I've got a sound triggered unit, in fact it's got all sorts, light, even a chrono so it can detect speed of projectile and dial in an offset in ms. But you don't need it unless you're using flash to freeze something fast like a pellet... i think when I shot Nick it was a dark day, i had no flash and I was on about 1/200th- perhaps 1/400th. For the vapour blast you don't need it.
For muzzle blast from firearms, i think I took just one on 1/4000th, and the rest were 1/1000th region. The online shots were on an old dead server so i'll see if i've got them on backup somewhere. But it's just timing rather than fast frame exposure. The DS3 only could do 5 fps from memory... I did use that burst but it wasn't held down, just jabbed when i thought the shot would be taken.
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