[MF3D.FORUM:1048] Re: Mounting issue

["Bill Glickman" <bglick@xxxxxxxx>]

Dick, David K, Paul, David L, Greg,

          Thank you all very much for the assistance you provided in my
mounting dilemnas... (as well as other MF stereo issues) Dick and David, I
thank you for the returned slides and yes, they mounted fine..... pseudo
issues..hmmm    this shocked me, I mean how hard can it be to find the left
and right shot?

           I am very happy to report, I finally got to the bottom of what I
think was happening to me.  What a strange twist.  With the two M7's up on a
the stereo bar, I took the shots as per John B formula.... when the
seperated chips were on a light table, I looked to the left on each one, and
determined the one that came from the left camera by the additional amount
of scene on one of the chips.  That became my left chip.  I mounted that
chip in the left part of the mount and then adjusted the other one
accordingly.... so how could I possibly have gotten them crossed????  Or
psuedo???  I found out how...

             Answer - The cameras did not always have their lenses
perpendicular to the stereo bar... so for example, the left camera could be
perfectly square to the stereo bar, but the right camera is pointing a tad
to the left.... however, that slight angle toward the left can make the
right chip see more of the left part of the scene.  So I would actually be
decieved by the chips.... and mix up the two chips. Amazing how many things
can go wrong using two camers vs. one!

           I need a way to assure my cameras are perfectly square to the
stereo bar... any suggestions?  I thought of shinning a light through the
back of the lenses on a wall and measuring their distances, but the pattern
would open wide quickly...so I could only do it real close to the wall?

           Anyway, I am happy to report that most of my stereo pairs from my
trip were successfull.  However, in an attempt to not show any black
shadows, I opened up as much as possible to prevent any shadows...in the
process, my highlignts occasional were a bit washed out, this of course got
magnified in the viewer and looked even worse....so the leseen learned is
never shoot scenes with greater than 3 stops exposure lattitude and better
to underexpose a tad vs. overexpose a tad....

           My other lesson learned the hard way is blown out skies look very
strange...hence it is hard to include skies on very overcast days... they
will wash out and make the scene look quite unreal.

Regards
Bill G