Actually, I did look at the numbers. Here's some of the numbers:
At macro resolution (1:2)
Olympus 90mm f2 Tokina 90mm f2.5
l/mm /(contrast% 30 l/mm) l/mm(contrast)
f center corner f center corner
2 40/(30) 36/(25)
2.8 45/(47) 36/(30) 2.5 64/(55) 57/(49)
4 45/(69) 36/(43) 4 72/(67) 64/(54)
5.6 45/(68) 40/(45) 5.6 81/(68) 72/(59)
8 51/(60) 40/(50) 8 81/(62) 72/(60)
11 45/(54) 40/(42) 11 64/(62) 57/(55)
16 40/(48) 36/(40) 16 51/(52) 40/(52)
22 40/(33) 36/(27) 22 45/(45) 32/(42)
32 - - 32 36/(31) 29/(24)
At 1:4, the Tokina resolution numbers increase even more relative to the
Olympus.
Any explanation? Any other reviews of the 90mm?
Thanks, John
On Wed, 1 Apr 1998, PCA Cala wrote:
> Hi again J. Williams:
>
> > I looked back in the review of the 90mm macro in Modern Photography
> > (8/87) and it appears to be decent but reviews of the Tokina 90mm f2.5
> > macro (MP 6/89) seem to be much better. Mostly excellent ratings versus
> > good ratings at the various apertures. Any opinions? Did they change the
> > test method?
>
> They did at about that time, which might account for the differences in
> qualitative wording. You shouldn't be looking at the words but rather the
> numbers! And keep in mind these tests are based on a single production
> sample. Besides testing in the center, the Modern Photo tests looked at
> performance in the corners - hardly the place most of us put critical subject
> matter. So take test with a grain of salt and try to evaluate the results of
> different testing methods before drawing conclusions.
>
> Gary Reese
> Las Vegas, NV
>
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