50 Summicron DR Update

[Stephen <cameras@jetlink.net>]

Well folks, after spending several hours with Modern, I found the
following:

8/83 pg 107  "Can you say what is the best 50mm normal lens for a 35mm
camera MODERN has ever tested?"  "We'd give the nod to the old 7-element
version of the 50/2 Summicron....rigid.."

12/83 pg 66 Clarification.  a letter in Too Hot to Handle:

I believe the lens you're talking about is the rigid Summicron lens made
from 1953 to 1956 and having 4 of its 7 elements made from lanthanum
glass, a rare earth glass.  I wrote to Leitz in Rockleigh, NJ about the
7 element Rigid Summicron to found out more information.  They replied
that the Rigid and Dual Range 50/2 Summicrons are exactly the same, the
only difference being the mount.  My question:  Is the Dual Range the
same lens and glass? If it is the same lens why does it not rate the
same as the rigid lens?  Is there anything wrong with the Dual Range 50
mm /2"

Modern's reply:

"First of all, both the 50/mm f/2 Dual Range Summicron and the "plain"
rigid 50 mm f/2 Summicron are essentially the same 7-element lens, with
rare earth glass elements as you state.  The only important difference
is the focusing helical, which gets you down to 19 in with the former
and 3 ft, 4" with the latter.  Both versions can accurately be described
as "rigid 50 mm f/2 Summicrons" as neither is collapsible.  Your
assumption that we were somehow slighting the Dual Range Version is
therefore unfounded.  As a mater of fact, the actual lens which topped
Modern's 50 mm lens test list happened to be a Dual Range Summicron,
through the 7-element non-close-focusing version provides, on average,
identical performance."


THE INTERESTING THING about the above is that Modern stopped short of
saying they were EXACTLY  the same formula, even though they could have
said so.  Instead, Modern used "essentially the same" and "on average,
identical performance."   Hmmmm.

I am not sure, I have not been inside the lenses and compared each
element.  But I am sure many people believe the formulas are slightly
different.

Stephen Gandy