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07-24-2013, 08:22 AM   #16
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QuoteOriginally posted by Ikarus Quote
I have a few lenses that are definitely not wide open when they claim to be
Ah, I see. Is there any way to tell this other than visually checking the aperture blades?

07-24-2013, 01:58 PM   #17
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QuoteOriginally posted by StevePrime Quote
Also, the longer focal length widens the DOF as well.
I think it is the other way around if the distance to subject is the same. However, for the same final magnification and f/stop focal length should not make a difference.

As for lenses not being fully open...for lenses with an aperture ring, I would expect that full-open should be full-open. At least that is true for everything on my shelf, including the Helios 44M.


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