Autofocus Enlargers and focus calibration

[cmiller@berkshire.net (Curt Miller)]

There's been some back-and-forth on this topic and I thought I'd throw in a
comment on autofocus enlargers in general.  I've owned and used, since 1969,
the same Agfa Varioscop 6X9 autofocus enlarger.  It has two matched lenses -
a 60 and 105.  This machine is an obvious copy of the Focotar but, unlike
most other copies of great objects, this one is actually of better
construction than the Focotar.  The 5 element lenses are spectacular
performers even by today's standards.  So quality isn't an issue.  Autofocus
is an issue though.  I learned early on that as well as the cams seem to
work, critical focus needs to be made (or should be) with each change in
magnification or new negative.  The gross focus is always good but for the
fine detail it pays to work the lens barrel focus.  The autofocus merely
gets me in the neighborhood.

The biggest diappointment with some AF enlargers is the inability to use
other manufacturers' lenses on them.  My 105 is too long to get me to 16X20
on the baseboard from 6X6 negs (ceiling height and column length are not a
problem).  I would give anything to be able to hang and Apo-Rodenstock 80 on
my machine but can't (don't know if Focomats have this same constraint).  I
just picked up a like-new Durst M601 with 50/4 El-Nikkor (not a spectacular
performer) for $150.  I'm having such fun playing with it.  I always loved
rack-and-pinion focusing (ala Rollei).  I'll put a good 75 on that and make
my 16X20s.

Another little autofocus hint.  I ALWAYS use (quality AN) glass carriers -
even for 35mm work.  I work clean in my darkroom so dust is not a
problem...so neither is negative pop and associated focus issues.


Curt

Elizabeth Mei Wong
Birding with Women Outdoors at http://members.aol.com/womenout/index.htm
           or with Berkshire County's Hoffman Bird Club

Henry Curtis Miller, M.P.A.

Pittsfield, Massachusetts
In the Berkshires, next door to Tanglewood