Re: Converging cameras...

[P3D <PgWhacker@xxxxxxx>]

>
>     The only reason to converge cameras is to not have to mask the on-film
>image at the sides.
>     If one is using 8 perf 35mm @ 36mm width, the widest mount available is
>33mm so image anomalies at the sides can be masked in mounting.
>     If doing something close-up with twin 35s(under 7-10 feet!) it's better
>to accept the image anomalies and mount in the narrower width mount as
needed
>to eliminate them.
>
>    


  Here's another reason:  to get the subject in both shots.

  My first SLR twin rig worked fine for indoor snaps of the paired bairns 
-- trouble was unless you took the photo from half way across the room 
there was so much parallax error right to left (3 inch inter lens 
separation) that nice shots in one camera ended up appearing in the other 
camera as hideous decapitations.  Switching to 28 mm lenses adds some 
coverage but makes for gnarly stretch.

    Now I've added a hinge to the leading edge of the twin rig mount, and 
I've calibrated the amount of convergence needed to center a subject a 
various distances.  Indoors, with 'infinity points' as close as the 
nearest wall, keystoning and other distortions have been so insignificant 
you can mount without trimming or masking.  And now the tiny tots show up 
in both halves of each stereo pair.

Greg







Greg Kane
Denver

PgWhacker@xxxxxxx





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