On Saturday, September 22, 2001 at 10:37, Walt Wayman <olympus@xxxxxxxxxxxxxxx>
wrote on "Re: [OM] F280 multi flash use," saying..
> On Sat, 22 September 2001, "Tom A. Trottier" wrote:
>
> > > > I wonder if the many flashes of the F280 in the Super FP mode have
> > > > ever been used to take multiple pix of something real fast, like a
> > > > bullet?
> > > >
> > > > Tom
> > >
> > > I did some bullet photography years ago. The trick is triggering the
> > > flash at the right time. We used two strands of very thin wire a
> > > couple of millimeters apart stretched across the path of the bullet
> > > and attached to the flash -- a Heiland Strobonar of some sort, as I
> > > recall.
> >
> > Used to use one of those potato mashers way back when.
> >
> > > When the bullet caused the wires to make contact, the flash went
> > > off.
> >
> > How far did the bullet go after triggering?
>
> Just a couple of inches with a .22 since the muzzle velocity of a
> long rifle round is only about 1300 fps. The bigger artilery went
> as far as 6 or 7 inches, especially the 7mm and .30 cal. stuff.
> We smeared lamp black on the wires, which were taken from an old
> electric motor armature, so they wouldn't be as obvious in the
> photos.
> >
> > > The gun (usually a .22, but we did try some larger caliber stuff)
> > > was secured in a vise, because this had to be done in the dark.
> > > After the lights were turned off, the shutter was opened, the
> > > trigger pulled, and the bullet took its own picture. Had to
> > > remember to close the shutter before turning the lights back on,
> > > though.
> >
> > But no multiple images, eh?
>
> No, that would require multiple flashes and some pretty
> sophisticated equipment. I don't know how fast the F280 fires,
> but I'd bet the bullet would be long gone before the second flash.
Since it syncs at 1/2000, it must do at least 5,000 flashes per
second for the exposure to be even,
If it did 5200 flashes per second, at 1300 fps the bullet would
travel about 3"
Each flash would be pretty weak tho..
>
> > Must have been loud.
>
> Yeah, but we were all shooters and didn't really notice it. we
> did it at night in a barn on our farm. The horses hated it and
> the chickens quit laying.
The risks of science!
Tom
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