P3D Re: Hummingbirds and sports

[fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)]

>It was a thought of how to take 3D shots of fast-moving sports such as
>football or baseball.... The action would be some way away,
>requiring the use of a twin-rig using telephoto lenses.

That's no problem... That's how Allan Griffin takes his sports
action shots... The cameras will have to be connected with combined
electric release cords.  The Konicas we mentioned and also a number
of other cameras, including my Minolta X-700, are triggered by 
electric shutter release cords and combining two of those will
let you fire both cameras by pressing one button.  

The only question
is, how well are the cameras synchronized.  The fact that they are
wired to fire together does not mean that they will be synchronized
at any speed.  There are small delays from camera to camera that
might throw them off-synchronization at the fastest shutter speeds.

Allan Griffin, who was a pioneer in this technique, has written a 
series of articles on now to test camera pairs (without lenses, open
backs and look at a uniformly lighted surface... test at different
speeds... if OK you should see the 24x36 mm film gate... in not OK
you will see only a fraction of it or even nothing at all).  There
is a good deal of literature on this, most of it in "Stereoscopy"
(magazine of the International Stereoscopic Union, ISU).

I have had good luck taking similar pictures with my twin Minoltas
X-700 at speeds up to 1/250 s. (Allan recommends 1/500 synch for
good action shots).

George Themelis


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