[MF3D.FORUM:1469] Re: NSA MF slide show

["Bill Glickman" <bglick@xxxxxxxx>]

David

       A Guide Number 300 flash will do the following...

300  Guide number of flash (in ft)
16    f stop lens setting
100   ISO

     With these variables, you can properly expose to these distances with
these fl lenses....  If you need more light, then fire two flashes, just
don't advance film if possible...or fire two flashes at once if you can, you
will double the distances below for two firings...

19 feet max. for 50mm fl
23 feet max. for 100mm fl

       Keep in mind - this is the max. distance an object will be properly
exposed, so closer distance may suffer burn out, not many people can fire
300 Gn flash, even a $1k top of the line Metz only offers about 145 GN.   So
if you can rig a remote control up, made by Wien, LPA design then put the
flash in the middle of the scene for best results, hopefully out of sight.
The easiest way is to use a remote control slave made by Wien, it has a
sensor on it that senses a flash.... so you put a small flash on your
camera, then put the big flash way out into the scene and when you fire the
shot, the remote always sees the first flash and immediately fires the big
flash!   Considering all this is working at the speed of light, it will
surely work within your 1/125 sync shutter speed.  I have successfully used
these for many years.... the only thing you need to be careful of, is that
no one else fires off their P&S camera with a flash when you rig it up to
go....you will waste a lot of bulbs!    The remote controls costs about
$40 - $90, the more expensive ones cover greater distance..... B&H sells
them.  Then you only need a small cable for connection assuming the flash
does not have a house hold connection which comes on the remote...

          BTW, where do you get these flashes that fire bulbs this powerful?
What is the highest powered bulb they make?  I was always interested in
these single use bulbs with awesome power....till now, I just carry 6
flashes with me and put them around the scene...

Bill G


> By the way, do you realize how much light is required to light
> up a cave when using a Spud at f16? I wish I had the $50.00 a
> pop for the MeggaFlash bulbs that have a GN of around 300-400.
> At least you don't have to worry about light leaks *{;-)
>
> David W. Kesner
> Boise, Idaho, USA
> drdave@xxxxxxxxxx
>