Looks like Roger at Lensrentals is no longer a hidden font of knowledge
requiring going to his website at Lensrentals or blog-- now has a deserved
wide audience even if in general don't exactly find the current forum where
they posted his article optimal.
The recent installment is quite interesting about 50mm lenses and contains a
bit of a history lesson.
https://www.dpreview.com/news/9236543269/why-are-modern-50mm-lenses-so-damned-complicated
As the Zuiko 50's are indeed double gauss-ish, his comments apply.
https://esif.world-traveller.org/om-sif/lensgroup/50mmf12.htm
As he mentions many aberrations don't improve all that much stopping down such
as 3rd and 5th order astigmatism, elliptical coma and others.
https://www.lensrentals.com/blog/2016/01/what-actually-happens-when-you-stop-down-a-lens/
This results in 50mm double gauss lenses of this era with odd situation that
a cheaper slower 50mm can outperform the expensive 50/1.2 stopped down.
Roger at LR:
"Unfortunately, that's not how it worked, at least not for double gauss lenses
wider than F1.4. Stopping down made them sharper, of course, especially in the
center.
But away from center they never got wicked sharp; they got OK."
That is no longer the case with very recent 50's depending on design though.
Is that the case with the OMZ 50's? I can't really tell from Gary Reese data
and I don't have a 50/1.2. Moose was probably correct about that lens that
unless you really need 1.2, for something, why bother? Still a cool lens. The
OMZ
50/2 macro seems to test better (Gary Reese) stopped down than the 50/1.4 even
but not sure that was statistically significant.
More 50's than know what to do with, Mike
--
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