Re: Allan Carrano comment on color slide film (Long)

[P3D Eric Goldstein <egoldste@xxxxxx>]

P3D Bob Howard wrote:

> As I said before the new glass available after WW2 made Tessar type
> lenses the equal of any and six and seven element fast lenses do no
> better, just have degree of freedom to reach f/2 or larger.

I've posted this before (from Phil Greenspun's photo.net), but it bears
repeating with regard to Bob's statement. My own tests on post war
Tessars and Xenars are in line with what Bob says, including the
reformulated and coated 3.5 tessars on the mid 50's east german
Belplasca.

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Here's something I found on rec.photo.advanced about a German magazine's
test of a (Yashica) T4 versus expensive ($600) Contax and absurdly
expensive ($900) Nikon P&S cameras (yuppie class): 

"The following is a side by side comparison of Yashica T4 vs Nikon 35Ti
and Contax T2's optical performance according to foto Magazin test
charts. 



                         Yashica T4        T2          Nikon  35Ti
         Lens:        Tessar 35mm/3.5  Sonnar 38/2.8    35mm/2.8
         Resolution  (smaller  better)
         Center:         0.017mm         0.015            0.015mm
         Edge:           0.017           0.016            0.018
         Contrast    ( higher  better)
         Center         92%               78%              72%
         Edge           85%               50%              45%
         Optical
         Performance    9.8               9.4              9.2
         Rating         *****             ****             ***


              T2 slightly better than 35Ti, but very close.

              T4's resolution < T2 at center and edge
                              < 35Ti at center
                              >35 Ti at edge

              T4  contrast,  better than T2 and 35Ti center/edge
              by subtantial margin."

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Incidently, I have a couple of T4s. Their tessars have been further
recalculated and more effectively coated than 50s/60s glass, yielding
truly excellent results (esp. for a $150 camera), as the numbers
demonstrate. They are not great to pair for stereo, however, as their
exposure automation tends to favour higher shutter speeds rather than
smaller apertures.


Eric G.


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