Archived posting to the Leica Users Group, 1999/10/04

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Subject: [Leica] Now Focomat 1C Question (was: Has the LUG a future?)
From: "Anderson, Ferrel E" <AndersonF@ria.army.mil>
Date: Mon, 4 Oct 1999 15:26:34 -0500

The Focomat 1C is worth saving.  It is a precision machine, and is a joy to use,
especially with the autofocus capability from 2X to 10X magnification range.
The autofocus requires a Leica Focotar or Leica 50 mm camera lens to operate
successfully.  You will also have to use a Leica or other brand 25mm thick
easeI, although this can be resolved by shimming up any easel thinner that this,
or by using a spacer on the locating pin on the column that positions the head
in relation to the base board or easel for thicker easels.

I would encourage your friend to find the condenser and negative carrier,
because they are expensive to replace new, and hard to find used.  If you are
not in a hurry, wait him out, or volunteer to help him find it.  He will
probably be so embarrassed, or his wife will be so embarrassed (much more
likely!) about the mess, that he will find it in a hurry.  Chances are that his
kids used the condenser to burn up bugs with focused sun light.  Any way, the
condenser and negative carrier are probably available from Leica, but at what
cost?  Probably too much.  Negative carriers are hard to find, but the search is
fun, and if you have patience, you will be successful. 

The Focotar lenses are excellent, especially in terms of contrast, i.e., in
their control of flare and color fringing from f5.6 on).  There are three 50mm
f4.5 Focotar optical  designs.  The first is a modified triplet, or Tessar or
Elmar design that uses 5 elements, with the front element split into two
elements.  it can be easily identified by the fact that the lens information is
printed on the front of the aperture ring (i.e., towards the easel when the lens
is mounted on the enlarger).  The second design is a Schneider design, and is a
five element, four component Gauss type.  The third design is called the
Focotar-2, and is a six element, five component  gauss Leica design of superb
performance.  These two lenses can be differentiated from the first design by
the fact that the lens information is printed on the side of the barrel.  I am
not knowledgeable about the performance of the Schneider designed Focotar, but
it is described by Leica USA as better than that of the first design, especially
for color work.  I have owned, used and tested the first design and the third
design lenses.  The Focotar-2 lens outperforms the first design in resolution at
every aperture, but especially at f11 and f16, and at every magnification from
2X to 20X.  It also outperforms the current 50mm Nikor and Schneider Componon
lenses in terms of edge resolution and contrast and lack of color fringing at
all apertures, and in overall resolution at the higher magnifications.  I have
not tested it against the current crop of APO enlarging lenses, but I can't
imagine any lens outperforming the Focotar-2.  The first design is an excellent
lens, and can be used for critical work at f8 at any magnification.  It is
designed for optimum performance at 4X, and the Focotar-2 at 8X.  I also own the
40mm Focotar lens, and can tell you that it is no match in terms of resolution,
especially tangential resolution, to the 50mm Focotar-2 lens.  However, I have
made B&W prints with both of these lenses at 8X magnification, and can see no
difference in the results.  We are talking here in terms of resolutions in
excess of 120 lpmm for both lenses.  A better comparison is that at f5.6, the
Focotar shows resolution in excess of 250 lpmm in both the tangential and
sagital orientations almost across the whole field, whereas the 40 mm Focotar
shows resolution that almost equals the Focotar-2 across the field in sagital
resolution, but drops to about 120 lpmm at the edges in the tangential
orientation.  From this aperture on, diffraction lowers the resolution and
contrast of both lenses, so that at f11  and f16 they show the same resolution
across the field.  I don't know about their performance in color enlarging, but
I suspect that the 40mm Focotar is better.

My Focotar-2 lens was purchased used with the proviso that the considerable haze
and dendritic fungus on internal elements could be removed.  The dealer sent it
to DAG for cleaning, and then it was sent by DAG to me.  I came to me in
excellent condition, with just a hint of haze that does not seem to affect its
performance.  DAG charged only $50 for the cleaning.  This is very reasonable. 

And yes, the lens can be used on any enlarger.