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04-06-2012, 01:28 PM   #16
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QuoteOriginally posted by lytrytyr Quote
Those tests are based on a perceived resolution,
which also factors in contrast to a large extent.
Thus a contrasty lens like the FA*24/2 is favored,
while a sharply resolving lens like the M100/2.8 looks poorer,
because it is less contrasty.

I have tried to set the record straight in my review of the M100/2.8:
SMC Pentax-M 100mm F2.8 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database
Yoshihiko’s lens tests are straight resolution only, see the link below for his procedures. He’s also testing these FF lenses on a film camera.


04-06-2012, 04:38 PM   #17

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QuoteOriginally posted by gofour3 Quote
Yoshihiko’s lens tests are straight resolution only, see the link below for his procedures.
He refers in turn to
PDML Lens Testing Procedure
The critical part there is the visual perception in Step 16.
This is the step where contrast becomes relevant.

Compare Yoshihiko's results with modern Imatest results
obtained by Photozone, Optyczne/Lenstip, et al.

Note the Photozone discussion of the FA*24/2.8:
Pentax SMC-FA* 24mm f/2 AL [IF] - Review / Lab Test Report - Analysis

QuoteOriginally posted by gofour3 Quote
He’s also testing these FF lenses on a film camera.
Right. For APS-C, the only relevant targets are those out to "C."

Since digital images may have their contrast enhanced in PP,
the visual perceptions analyzed with analogue techniques
no longer have direct relevance (although some conclusions may still be drawn).

As I've mentioned, the most striking discrepancies seem to be
Yoshihiko's overestimate of the FA*24/2,
and his underestimate of the M100/2.8.

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