P3D Re: Tessar & Xenar!

[Eric Goldstein <egoldste@xxxxxx>]

> Eric G. goes on to say "..the Germans don't play fair
> either, as the Tessar and Xenar are 5 or 6 element versions of the
> Planar."

Whoops! As usual, I probably didn't do a very good job of putting what
little is in my brain down on the keyboard...

You are absolutely correct, Bob. Tessars/Xenars are the four element
extension of the Cooke Triplet; it's the Planars which can be 5, 6, or
in retrofocus 7 element lenses. As they say, the fingers are the first
thing that goes... Or is it the mind? Can't seem to remember...

Anyway, I have seen Xenars referred to as "modified Taylor-types"
ackowledging the adaptation of Dennis Taylor's brilliant turn of the
century design.

> (A nice "Tessar" is the Ross Xpress, which is a Tessar with a three
> element rear lens!)

This is an excellent lens! More highly corrected than the Tessars/Xenars
with vitually no additional loss of contrast (cemented triplet at the
rear).

Sorry for any confusion...


Eric G.


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