Re: [APML] Tessar f/3.5 210mm - any good?

[Ray Butler <ray.butler@nuigalway.ie>]

I don't have that lens, but I have three other Carl Zeiss Jena lenses 
and they are all superb. They are late (multicoated) versions for 6x6cm 
cameras (Pentacon-6/Kiev-60/Exakta-66): Biometar 120 f2.8, Sonnar 180 
f2.8, and Sonnar 300 f4. By the looks of the serial number you quoted, 
your Tessar is probably single coated?

As Joe said, the Tessar is a 4-element design. It was prone to 
aberrations at f2.8, so f3.5 became its normal maximum aperture. Many 
regular photographers with 80mm f3.5 Tessars on their Rolleicord 6x6m 
TLRs speak really highly of the optical performance, even wide open. So 
you could look up reports of that lens and use them as a guideline 
(making allowances for the somewhat smaller 6x6cm film format). Later 
Rolleis and Hasselblads used the 5-element Planar design by Zeiss 
Oberkochen (which was actually first brought to market in the 1950s by 
Zeiss Jena, and called a Biometar by them). With 5 elements, this design 
could be opened up to f2.8. The Schneider Xenotar, encountered in MF and 
LF cameras, is very similar. (More recent Planars and Xenotars have as 
many as 7 elements, for top-notch wide open performance, but at a price!).

The 5- and 6-element Sonnars can be f2.8 or even faster, but they are 
_very_ heavy in large sizes as they use some very thick and wide glass 
elements. But I digress...

So I think your Tessar may be rather nice at f3.5, but it will probably 
pay off stopping it to f5.6. I have a few f3.5 6x6cm lenses, and good as 
they are at f3.5, when I look at the same picture taken at f5.6 I am 
always more satisfied with the edge sharpness, which by then is almost 
indistinguishable from the centre sharpness. The eye is always drawn to 
mildly aberrated stars away from the centre, such as I get at f3.5. Mind 
you, these are all wide-angle lenses (fisheye to wide-normal), so your 
Tessar short telephoto might be more forgiving.

Ray "Hi, my name's Ray, and ... I'm a lens-aholic" Butler


Gil McFarlane wrote:

> I have the above lens, and am considering making a
> camera for use with 4x5 sheet film.  I expect I'll
> need to stop down to about 5.6 (but would rather not).
>  Does anyone have any experience with this lens?  (it
> is a Carl Zeiss Jenna, #3873179.)
> 
> Thanks,
> Gil
> 
> 
> 
> 	
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-- 
Dr. Ray Butler (ray.butler@nuigalway.ie || ray@physics.nuigalway.ie)
Lecturer, Dept. of Physics || Computational Astrophysics Laboratory
National University of Ireland, Galway, University Road, Galway, Ireland.
Tel: +353-91-524411 ext. 3788   FAX: +353-91-525700

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