A kind favor from a forum member owning the CV 28 3.5 and a digital body for it...

[Juan Valdenebro]

Hello,
I was wondering if someone ever did a test on this, or if someone would be as kind as to do it... It takes 5 minutes... I want to know at which aperture diffraction appears on a CV 28 3.5 and starts making less sharp the center of an image... I have no digital body for my CV 28 3.5 and I can't check it with ASA400 film... A digital body is the way to do it well... Somewhere years ago I read diffraction appears differently in different lenses depending of lots of factors related to lens speed, type of front element and internal design... 4 shots at f5.6, f8, f11 and f16 are enough to check it...
Thanks a lot!!!

 

[slidesandthecity]

Even though I'm not the OP, I'd like to you thank you for posting this. I have a 28 3.5 on its way to me and was curious to see this comparison.

 

[Juan Valdenebro]

That's very kind of you, funkydog!
Did you test 3 different CV 28 3.5's?
What's your general veredict on sharpness loss beyond f5.6?
Cheers,
Juan

 

[Juan Valdenebro]

Well, this has been great help...
I guess f11 can be used without worries, and in my case (ASA400 b&w film), differences just won't be visible...
I wonder if the case will be the same with close focus, 2-3 meters, as usual in my street shooting...
Thank you very much for sharing all this!
Cheers,
Juan

 

[jonmanjiro]

I just tried this with my R-D1x and I'd agree that the Skopar doesn't seem to show diffraction at f11. Here's the unedited jpg files as they came out of the camera - f5.6, f8, f11, f16, f22.

 

[Juan Valdenebro]

Hey!
I really appreciate your test, Jon!!!
The tiny skopar offers a very decent f11...
Thanks!

 

[V-12]

Using my 28mm 3.5 on a Leica Monochrom and I'd agree that up to f/11 the CV is a truly excellent lens, beating the Leica 28mm Summicron for sharpness in the corners at its widest f/3.5 aperture and easily matching it for sharpness across the whole frame at all apertures...until f/16 where both suffer from diffraction but the Leica creeps ahead. But I'd still use either of them at f/16 if the situation required it, its not like the diffraction suddenly gets catastrophic.

V