[MF3D.FORUM:761] Re: I need a MF 3D Dr.

["don lopp" <dlopp@xxxxxxxxxxxxxxx>]

 Sorry. I jumped to soon the last part showed  up in the next message - I
need to be more patient Don
----- Original Message -----
From: "don lopp" <dlopp@xxxxxxxxxxxxxxx>
To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
Sent: Wednesday, June 14, 2000 10:18 PM
Subject: [MF3D.FORUM:740] Re: I need a MF 3D Dr.


> >From my experience assuming that your Mamyia 7 are 160 mm long, the
closest
> you can be with 50 mm lenses is 16 feet and 25 feet with 80mm lenses which
> amounts to  1:30 for the 50mm and about 1:45 for the 80 mm lenses these
> numbers work for me in the past but with my fuzzy methadone mind I might
be
> all mixed up. Good luck Don.
> ----- Original Message -----
> From: "Bill Glickman" <bglick@xxxxxxxx>
> To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
> Sent: Monday, June 12, 2000 11:40 PM
> Subject: [MF3D.FORUM:726] I need a MF 3D Dr.
>
>
> > Hi folks, I just finished my testing.... need help again... just can not
> > seem to get stereo images to fuse, when using two cameras following John
> B's
> > formula.  Here is my problems
> >
> > 1.  I am using two M7's with perfectly matched 80mm lenses.  When I use
> each
> > camera seperately and shoot the left and then a right shot with 65mm
lens
> > spacing it works perfect every time.  True with both cameras.  This
worked
> > perfectly before Alan modified my viewer and also after he modified my
> > viewer, so no change.
> >
> > 2.   When I use both cameras simultaneously on a slide bar with inter
> ocular
> > spacing as per John B's formula, I can not get the chromes to completely
> > fuse.  I followed the formula to a T...had a tape measure with me, and
did
> > NOT violate any aspect of the formula or stereo base.  I have the same
> basic
> > problem...I can not get all subjects in the scene to fuse at once.... it
> > seems they will all fuse, but seperately.  I fuse one subject and loose
> > another.... then when I fuse certain ones, I start getting the double
> edges
> > on the left and right again.  (a lot of this double edge image seems to
> have
> > cleared up after Alan Lewis corrected my viewer lens spacing)
> >
> > 3.  When mounting the chromes, I notice something odd.... when Paul
Talbot
> > was here, he showed me the use of the mount gauge.  Setting the nearest
> > subject to the near line and furthest to the far line.... Both can NOT
be
> > satisfied at once with the John B spacing.  (Is this normal? )  And it
> does
> > not matter if I mount to the near or the far, I still can not get
> everything
> > to fuse at once.
> >
> > 4.  Greg Erker advised to take one camera for the left shot and then
move
> it
> > over and bring the other camera in for the right shot, maintaining 65mm
> > interocular spacing.  I felt this was an excellent "process of
> elimination"
> > test.   I did this, and voila it works.  That is why I wonder if the
> formula
> > could be ill advised.  Here is some examples of the near and far in feet
> and
> > the stereo base in inches I have been using...
> >
> > N   F     Base "
> > 10  26    6.5
> > 10  23    7.1
> > 10  20    8.0
> > 10  17    9.7
> > 10  14   14.0
> > 10  13   17.3
> >
> > Maybe the formula needs tweaking???  I doubted this since so many people
> > including David Lee have used this successfully?
> >
> >     Some basics, I am focussing on identical subjects, same f stops,
> > simultaneous shutter firing, I am using a Jaspar engineering 24" stereo
> bar
> > with built in level, I checked the left / right part of the level with
> > another level, it is true, I always level the shot left / right, but
> > sometimes tilt the camera down for a scene.   For this test, there was
no
> > infinity in any of the shots.
> >
> >     After I concluded that the mounting gauge would not work, I mounted
> the
> > left chrome and moved the right chrome up and down till things fused
> > verticaly, pretty easy to see that.... then I moved the same chrome left
> and
> > right, and no matter how many places I put it, I can not find one place
> > where everything is fused!  I was viewing this over a light box with the
> > viewing lenses from my Saturn viewer.  I just removed the lens panel and
> > used it for a viewing aid since this would duplicate what I see in the
> > viewer.
> >
> >      One other tid bit they may help someone diagnose my problem.  One
> shot
> > of a small waterfall in my backyard with larges stones sticking out, (as
> > steps for the water falling)  seem to appeared backwards.  In other
words,
> > instead of the rocks sticking out at you, they seem to be inverted, or
> > pulled backwards, like they were indented vs. protruding?  That was
> strange,
> > but I felt it may provide a clue to solve my never ending mystery.
> >
> >   I am leaving for a long photo trip and have been trying to get this
> worked
> > out for the past 6 weeks but just keep failing.  Any input would be
> greatly
> > appreciated.  Thank you all.....
> >
> > Regards
> > Bill G
> >
>