Re: Flash Fluke? (fwd)

[wier@xxxxxxxxxxxxxxx (Bob Wier)]

>From George T. during the outage...
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>Subject: Re: Flash Fluke?
>Cc: photo-3d@xxxxxxxxxxxxxxx
>Reply-To: fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)
>Subject: W-POB88 KEYWORD
>X-Loop: bobcat.etsu.edu
>X-Loop: pobox88@xxxxxxxxxxxxxxx
>
>Hi Chris!  Nice to hear that you got great results in your first flash
>pictures.  3-D and flash go very well together.  And using a flash in the
>Stereo Realist is very easy...
>
>>(1) I filed off a bit of my flash's foot because it was too wide to fit in
>>the Realist's bracket.
>>(2) I filed off the nice soft brass(?) button in the middle of the Realists
>>flash holder.
>>(3) I checked for synchronization between the flash and the camera shutter.
>
>The Realist is synchronized in all speeds.  I have done (2) in all my own
>Realists.  (1) is required in some flash units, not all.  Also, you could
>bend the sides of the Realist shoe.  Also, having the flash go too far in
>can be a problem, easily solved by placing a stop in the back of the shoe.
>
>>(7) The Results.  All of exposures were right on (as best I could tell) as
>>long as the flash was pointed directly at the subject!  This was true for all
>>shutter speeds--1/150 down to 1/2 sec.  I even had the subject move
>>intentionally during the 1/2-sec exposure to give the flash a "freeze" test.
>
>Sounds good!  Bounce flash is hard to do... You lose too much light.
>Perhaps it is nore important in 2-d than 3-d.
>
>>The flash froze the moving subject during 1/2-sec exposures.  The flash gave
>>proper exposure for all shutter speeds.  How can this be?!
>
>Simple:  The flash light output has a very short duration (much shorter
>than the Realist's top speed) and all the light is reaching the film, no
>matter what the camera shutter speed is.  It is only the aperture that
>counts.
>
>>So, is this a magic flash because of its thyristor feedback circuit?  I'd
>>like to hear other people's experiences.
>
>My Minolta PX360 flash never misses exposures in Auto mode.  What surprises
>me is that, in theory, the auto-flash should overexpose the subject in a
>dark background and underexpose it in a bright backgound.  In practice, I
>have found that the exposure works well in both situations.  Flash shots
>can also be very sharp because camera shake is not a factor.  Darkening the
>background is an extra plus in 3-d with flash...
>
>George Themelis (photo-3d list, please come back!)
>
>



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