[Rollei] A Very Brief Primer on Lenses

[Marc James Small <msmall >]

At 07:25 PM 4/24/2001 -0400, Jim Hemenway wrote:
>I'm very happy with my 2.8F. It is said to do a better job wide open
>than the 3.5s but I don't think that you'll notice much difference
>unless you print very large and maybe not even then depending on the
>aperture used
>
>The 2.8F has the mirror in the WLF, I don't know about the others.

Well, "received wisdom" is that the 3.5 Planar or Xenotar will outperform
the f/2.8 lens save, obviously, for apertures wider than 3.5.  But I have
concentrated on the 2.8's for some years now, and a GX is my daily driver,
having even supplanted my much-beloved collection of Leica RF's.  In
general, it is probably fair to assess the capacities of the lenses along
the following schemata:

Triotar	Zeiss three-element lens.  Okay, but not a sterling perfomer.  Used
in Rolleicords to the III.

Tessar/Xenar	Zeiss or Schneider.  Four element lenses from an epic design.
These can be further broken down:

Uncoated Jena Tessar	a landmark lens in a landmark camera, but the
performance will be soft at wider apertures and will lack the fine
resolution of later lenses.  Good contrast, though.  Used on all "big"
Rolleiflex cameras from the original Standard through the Automat, Type
III, and on the original "Black Baby".

Coated Jena or Oberkochen Tessar 	Coating improves contrast in contre-jour
conditions.  A fine lens.  The Oberkochen lens was possibly a VERY slight
reworking of the original design, though I've not seen any difference in
performance.  Used from the Automat, Type III, to the 3.5B/MX, and on the
2.8A.  A recomputed version of this lens was used on the Rolleiflex T.

Xenar	Schneider's version of the Tessar.  Similar capacities.  Used on the
3.5A and B, the Rolleicord IV, V, and Va, the Rolleimagics, the Postwar
Babies, and on the final run of the T's.

Planar	Five-element Zeiss lens, an epic design.  Used from the 2.8C to the
current GX and on the 3.5C/MX-EVS to the 3.5F.  A Jena version of this
lens, the Biometar, appeared briefly on the 2.8B.  The 3.5/75 Planar was
recomputed to accomodate a sixth element to improve edge definition and
illumination from lens s/n 2,753,002 in the 3.5F, Type 3, and on the 3.5E3.

Xenotar  A Schneider lens similar in performance to the Planar, though of
slightly different construction.  All Xenotars used in the 3.5F, Type 3,
and the 3.5E3 were of six-element design similar to the recomputation of
the f/3.5 Planar.

There was also a Distagon used in the Weitwinkel-Rolleiflex and a Sonnar
used in the Tele-Rolleiflex.

Marc

msmall    FAX:  +540/343-7315
Cha robh bas fir gun ghras fir!

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End of Rollei Users list digest V9 #150
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