Flash Duration…..it’s no biggie

12 07 2013

once in a while photography comes back to its roots and gets all antsy and technical. advertisers just love this. they can mix the lies with the truth and Nobody will Notice, because they are too busy arguing on the internet about stuff that Really Doesn’t Matter. it’s almost painful to watch.

anyway, my main thrust here is a  bunch of flash makers saying Mine is Bigger (actually Smaller!!!) than Yours. Flash Duration is the buzzword…..the tiny fraction of a second during which the flash is burning and casting light on the scene. Oh our Flash Duration is 1/30,000 of a second. beat that. ner ner ner nerrrr nerrrrrrrr.

if you are photographing a scene where the only source of light is the flash, and it burns for 1/30,000 of a second, it’s equivalent to using a 1/30,000th shutter speed. which no-one can at the moment. here’s a shot, with flash, at 1/2500 of a second (that’s the shutter speed) – the flash duration in this one is 1/6500th. the duration of the flash Needs to be shorter than the shutter speed, otherwise the flash will be burning when the shutter is closed, which is pretty dumb, if you ask me.

Musicians jumping in the air don’t really move that fast….1/2500th is probably overkill but I was looking to darken the background a bit. the only time that flash duration is crucial, is where the subject is travelling at a super high velocity. what would that be? a bullet from a gun? arrow in flight, something along those lines. so I guess if you do a lot of scientific photography, bullet velocities and trajectories then yes, the Profoto D1wankalot is probably the best masturbatory tool you can get

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