T3D Viewer lense focal length

[cfholzner@xxxxxxxx (Chuck Holzner)]

I have been shooting stereo for almost a year now. I would like to be able
to take a picture and later bring that slide back to the spot where it was
taken and compare it to the site to see differences in the site.  I am
shooting Realist format (all my cameras have 35MM lenses) and have a
Brumberger viewer( I know it isn't the best). I have been using Velvia
film. I can never see all the detail in the slide that I see with naked
eyes at the site.  I believe that much of this loss of detail is due to the
fact that the view in the viewer is smaller by about 2/3 then the view of
the site directly. I used one eye in the viewer and one directly to compare
sizes.
In "Stereo Photography" By Feitz Waack, Page 17, "In the ideal case, the
optics within the viewer should have the same focal length as was used
during exposure."  I believe my viewer has 45MM lenses and mismatch the
35MM lenses of my cameras making the view smaller.  I have been shopping
around for a viewer with 35MM lenses but have not found one. Aparently
Realist, Revere and other makers of viewers never read that book. When I
ask venders if one is available I am told that they don't know of any and
that it would be very hard and expensive to make one with that short a
focal length that would view the slide edges.
Does anyone have experience with this problem they can share?  Does anyone
know of a realist viewer with 35MM lenses?  Am I barking up the wrong tree?
Perhaps this is why the Euro format cameras with longer focal lengths are
so wanted.

Chuck