I'll try not to bring up the term "3D" in this exchange. It's a word that I feel is over-used. To be frank I think that I nearly hate myself from expressing my feelings in this thread. Sometimes I feel like I see things that just aren't there. But then I can't also deny, as Lenstip's focusing scale tends to show, and other examples here and there, such as Marianne Oelund's thread on DPreview, that lenses do indeed vary quite considerably in the way they render transitions from sharp to blur. And I can't deny that I find shots like these, well, let's say, aesthetically challenged in the blur department :
https://3.img-dpreview.com/files/p/sample_galleries/4037492029/4652016161.jpg
https://www.magezinepublishing.com/...hres/a-50mm-lens-bike-4P2A0426_1536166554.jpg
I mean, those double images as soon as one leaves the centre, or the nervous rendering of the bicycle's front wheel and handlebar are plain evil to my eyes. I believe that most lenses would struggle here, but that exactly where I'm expecting Canon engineers to work their magic for a 50mm f1.2 €2500 lens.
If I may do so, this is what I see in this picture :
View attachment 181169
What I feel is that, to some extent, the subject is in front of a painted canvas. I'm lacking here a certain transitional quality, which some lenses are able to better convey (although at this aperture it's normal that the background becomes unreadable at some point).
It's as if this photo has three very defined, different stages : sharp as f!ck, then a very short, slightly nervous transition zone, then blur with sharply defined edges to the blurred areas.
It's difficult to criticise the 35mm II, because, in a way, it's a "perfect" lens. I guess that this is exactly how a lens is supposed to behave. And in many ways it's a lot better looking than a lens with over-corrected spherical aberration and onion rings, or double lines bokeh.
Years ago I was after "perfect" lenses like this (or at least as good as I could get them then), because relatively speaking, they behaved better wide open than other lenses that were just sub-par, with onion ring bokeh, etc. I used to use a 50mm Makro Planar instead of Nikon's cheap AF-D 50mm lenses because it had a more neutral and controlled bokeh at f2 than the Nikons, throughout the frame. But these days, I feel that lens designers seem better equipped to fine tune the aberrations of a lens to purposefully bias the bokeh rendering towards the rear without excessively affecting other areas of performance, and I think that I'm after those lenses right now
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I think you're right to nitpick
. Your observations are valid and I agree with you. It's difficult for me to exactly nail what I see in these pictures that I find objectionable. Perhaps it's less the amount of blur than the sharp edges around the blur that troubles my mind. In the first crop you're right to highlight that the strap on the guy in the background is blurrier and more transparent indeed. But the edge of the strap fades into the black shirt just as rapidly as the strap in front. Perhaps it's that.