Re: 220 VR questions

[simon nathan <simonwide@xxxxxxxxxxxxx>]

dear bill-
how come mamiya lenses work on the hulcherama? read my previous comments
on list re image smear. simon nathan

Bill Glickman wrote:

Hi, I am new to the Pan list...

     I just bought a Seitz 220 VR.  I have been testing it for the past week
and trying to perfect the use of it before I leave on a long Photo trip on
6/16.  I have the followings issues that possibly more experienced users
could be so kind to assist me.

1.  The h value (H-H) which seems to be the distance between the two nodal
points of the lens.... this information seems impossible to get for the
Mamiya 645 lenses.  Seitz does not know the values and Mamiya either won't
release the information or does not comprehend exactly what is being asked.
I am wondering why Seitz even designed and released the Mamiya lens board
when these values are unknown by them?  Peter Setiz recommended using the
Hassy values which are in the manual, however, the variance in lens makers
values for equal fl lenses for this value varied so much between the 35mm
lenses, like Nikon, Leica, etc.... I felt doing this would be a total random
guess which could be so far off it would make things worse?

2.  Does this h value offer no benefit when subjects are far?

3.  Mr. Seitz explains the need to nail the fl of each lens down to +/- .05
mm.   With my 150 and 300 mm this process was tedious but, it seems to have
worked.  I shot a wall about 150 ft. away.  I measured the aspect ratio of
the wall, and then measured the vertical height on film and calc. what the
horizontal needs to be to maintain the same aspect ratio.  This was fairly
effective.  However, on wider angle lenses, 80 and 35mm, this was not so
easy... image distortion makes measurements too difficult to be this
accurate.  Mr. Seitz said shoot letters.... so I shot letters on buildings,
the largest letters I could find.... and it is way too difficult to
determine within .05mm which letters look best.... they all look good when
you get down to a few tenths of a mm?

4.  The test images I shot all appear soft on film.  I was a disappointed
with the image quality.  It did not come close to what a MF camera can
produce.  Do other people experience this also?  I was told by a few users
that rotational cameras are not that sharp for the obvious reasons.  Mr.
Seitz said a MF lens will never be as sharp on a rotational camera vs. a
still camera?  I am wondering how much worse the image really gets.  Does
using smaller slits help?  Any input on this would be helpful...  I was
planning on big enlargements, and now am doubting the possibility of doing
such.

           Thank you for any help you can offer.  This experience is turning
out to quite a circus act so far...  Although Peter Seitz has emailed me,
his answers are very very very short and sometimes inconclusive.... that is
making this process go on for a longer time than it should.

Regards
Bill G