[Leica] Rose Scollard and the Visoflex

[editor at frontenachouse.com (Rose Scollard)]

Well, ask I shall, indeed!  Thank you so much for taking the time to supply 
so much information.  I am grateful and overwhelmed in equal measure.  D/
----- Original Message ----- 
From: "Marc James Small" <marcsmall@comcast.net>
To: "Leica Users Group" <lug@leica-users.org>; "Leica Users Group" 
<lug@leica-users.org>
Sent: Saturday, November 04, 2006 8:15 PM
Subject: [Leica] Rose Scollard and the Visoflex


At 09:21 PM 11/4/2006, Rose Scollard wrote:
>wow - that's a lot of variables!!!!  thanks for the link.  David

Rose

There are hundreds of adapters for Visoflex, many
of them not readily known as they were marketed
through the microscope side of Leitz and not
through the camera dealers.  To complicate the
issue, Leitz used three different sets of
catalogue codes -- the alphic one such as OUBIO
used into the 1960's and the current numeric code
(which has several permutations, but let that one
rest for now!).  In addition, Leitz was beginning
to convert to yet a third system, numeric, when
the Second World War broke out, which forced them
to stay with the alphic system they had been
using.  Still, catalogues and the like from the
late 1930's list both the alphic code and the
numeric code from this abortive system.  This
switchover complicates things more than a bit, as
many of the adapters were in production from the
late 1930's to the untimely and unseemly death of
the Visoflex system in 1984.  I have been
compiling a list of Visoflex adapters for the
past decade and I would guess that it is only
about half done, as I have yet to work my way
through the process of acquiring and analyzing the microscope catalogues.

There were two basic families of Leitz reflex
housings.  First came the PLOOT, in two versions,
and the Visoflex I, which could be had in both
LTM and M BM.  This had an optical registration
of 62.5mm (that is, it required lenses with a
back-focus which could accomodate the camera's
depth plus this distance -- that is, 28.5mm +
62.5mm, for a total back-focus of  91mm.  (The
lenses stayed the same:  M mount Viso I's were
actually 63.5mm in depth, as the depth of an M
camera is 1mm less than the LTM bodies to allow
the use of lens adapters of 1mm thickness.)  Then
came the Viso II, IIa (two versions, yet again),
and III, which only had a depth of
40mm.  Something had to make up that 22.5mm
difference, and the OUBIO was the solution, as it
is, essentially, a 22.5mm spacer.

Later Visoflex lenses were made a bit longer to
accomodate this.  I suspect there are exceptions,
but a good working hypothesis is to check on how
the lens is marked:  if it is in cm, it requires
as OUBIO and, if it is marked in mm, it does
not.  But that is a working hypothesis I just, as
Mark Rabiner might say, just worked out in my
head, and I've not checked all my Viso lenses to
be certain of this -- I just strongly suspect this to be the case.

There is a lot of Visoflex knowledge on the LUG,
and a bit of Visoflex deriding, as well.  Bear
with it:  the Visoflex allows all sorts of
flexibility with a Leica camera, such as macro
work (20X enlargements, for instance) and tele
work -- I can readily adapt my M6 to one of my
telescopes and get a 2100mm long-focus lens!  It
is a system well worth learning.

Ask, and we shall do our best to answer.

Marc



msmall@aya.yale.edu
Cha robh b?s fir gun ghr?s fir!

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