I see, so a prime vs prime comparison would be more fair. He did do that for the original article in The flattening of modern lenses or the death of 3d pop — YANNICK KHONG but only provided two samples. Personally I only see a difference in color cast between the two lenses.
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It would be impossible to do a fair comparison. There are thousands of lens models and they all render differently. To determine that it’s element count rather than something more complex would be impossible. To logically disprove the thesis I guess all you have to do is find a complex lens that renders spatially rich images. In my mind this has already been done.
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Regarding https://yannickkhong.com/blog/2015/11/12/depth-vs-flat-lens-quick-comparison: Hmm. I downloaded the “Comparison 3: 55mm (6 vs 16 elements)” images. Here is a crop from each:
Yes, there is a clear difference: the left image is muddy, fuzzy, lacks micro contrast, call it whatever you like, compared to the right image.
BUT the left image is the 55mm AIS, the right image is the 24-85mm zoom.
I suppose the author of that page didn’t look objectively at the results, but just showed the crops that supported the contention. I suspect the difference between this pair of images isn’t the lenses, but what they were focused on. The zoom lens was focused on a greater distance than the 55mm. So the 55 gives a better image of the foreground car, and the zoom is better for distance trees.
Don’t take my word for it; download the images and make your own comparisons.
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Usually the elementcounters look for a sense of depth not resolution or lack of aberrations. More elements can obviously result in better corrected images.
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Good catch, indeed the zoom looks better. I don’t think the focus is the issue here as he mentioned manually focusing the lenses in live view at maximum magnification, surely he would have focused on the same subject.
The whole “3d pop” discussion is shrouded in mystery and opinion… just my opinion. 
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Yes, I noticed the text claimed that. But I also see the images, and mis-focus is the obvious explanation. But it may be something else. The text does mention that:
My hypothesis is: the DoF is the same, but the lenses were focused at different distances.
There is a similar problem with “Comparison 4: 85mm (6 vs 16 elements)”.
Left: 85D. Right: 24-85VR zoom.
The 85D has better sharpness on the foreground car (and especially the very-foreground foliage). But it is worse for the distant foliage and fire hydrant sign.
I should mention that the images I show have been JPEG-compressed twice, so beware of drawing conclusions from them.
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I’m still really enjoying learning on my bridge camera, but as I look to my side I can always see my Minolta goading me on…
It’s the Maxxum 7xi SLR and it has the 28-105mm af xi lens on it, which means that if I wanted to use that discontinued lens I’d be considering a used Sony a65 (I think). I haven’t found (haven’t looked too much) info about which DSLR body’s are compatible with the Minolta A mount xi variants yet.
That’s the only vintage glass that I have currently, but being a budget conscious (*cheap) enthusiast, I’m sure I’ll end up gathering more in time.
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I don’t know much about that either - but I know that Sony mirrorless cameras can use the Sony DSLR/SLT lenses via adaptor, complete with AF. So if those Minolta lenses are compatible with Sony DLSRs, you could probably go the mirrorless+adaptor route (an early A7 body doesn’t cost that much) which would give you loads more options for other lens mounts via adaptors. The mirrorless’ short flange distance means almost anything can be adapted to it.
Just a thought from someone who nknows nothing about Minolta lenses.
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I think it is just a misunderstanding that comes from not learning about field curvature.
TL;DR:
- field curvature is the manifold where objects are in focus
- it is not necessarily a plane, hence the name
- consequently, photographing objects in a plane and comparing focus is a pretty useless exercise
- different lenses have different field curvature (both between- and within models)
- field curvature can be used to the photographer’s advantage once understood
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I guess there are degrees of lens nerdery and some may not be aware. In general though many 3d pop & microconstrast folk are very aware of such basic optical properties. The battles of defining exactly what 3d pop is and what complex set of properties make it happen are probably raging somewhere on the internet as we speak. I doubt it will ever be fully settled.
I think different lenses undoubtedly create different looks. Photography is clearly in a cinematography phase where we’re catching up on what people selecting gear for movies have been doing for decades. Lenses are now often good enough performance wise other properties are getting explored by manufacturers and users alike.
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I am not sure I agree. In the 3d pop & microcontrast comparisons I have read I have never seen any results about lens field curvature. They just compare crops without digging into the cause of the differences (if any).
IMO it would be much better to provide details about the optical properties of each lens first, especially field curvature, and then go to the crops. The reason for this is that a very subtle field curvature (causing a slight, nearly imperceptible defocus around a subject) can make the the latter “pop”.
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This is the only channel/video I’ve seen that mentions this topic, although he doesn’t connect it to how the bokeh will look based on those properties.
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We’re seeing it in different contexts then. I’ve barely seen anyone using crops. It seems like a terrible way of appraising 3d-pop, a quality (to the extent it exists) is about the whole frame.
Maybe it’s unusual on youtube but shooting close to ground and using find edges equivalent is imho a well known technique.
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Eg see this famous blog (which has been linked here before). The page is full of crops. And, incidentally, I could not find any mention of field curvature. Just rants about glass being evil.
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I can’t see a difference in all those rabbit photos, is this something like the emperor’s new clothes?
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In addition to the many good comments, I’ll throw in my $0.02 worth. Keeping mind anything I say is worth the price you paid for it (ie: $0).
From looking at lenses for going on four decades to find a certain “magic”, here’s what I’ve learned.
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Until surprisingly recently, lens designers I’ve talked with felt that correcting for 7th order effects, while “do-able”, was a little over the top. People told me it was “unnecessary.” Modern optics can be corrected for 11th or, gasp, 13th order effects. There are a few interesting reasons to do this now.
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In general, vintage lenses typically were designed for either resolution or contrast. Modern optics can be found that strike an interesting balance between resolution and contrast (see previous paragraph). Which leads me to think the computing required to design lenses for 11th order effects was rather too great for rooms filled with human calculators (see Nikon’s 1000 and 1 Night series).
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In the vast majority of imaging systems I’ve looked at, resolution limitations are found in light sensitive materials (ie: film or digital sensor) and not in the lenses themselves when operating at their optimum aperture. OK. That’s a strong caveat, but someone sent me years ago a 75mm f/8 wide angle lens that covers at least 4x5 inches that is diffraction limited from wide open. So “softness” at wide apertures for some vintage optics is there because they’ve been designed this way.
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This is why I feel many vintage lens manufacturers designed their optics to a customer base (sort of). I’m thinking of old Nikon optics where they were designed for under-corrected spherical aberration behind the point of focus as well as providing a veiling spherical aberration wide open. This was, I’m convinced, deliberate to satisfy the Japanese market which valued a “delicacy” of rendition. Canon OTOH went the over way because of their customer base and over-corrected for spherical aberration behind the point of focus. Old Canon lenses can appear sharp wide open, but deliver nasty soap-bubble-ish background rendition as a result. Pentax, again in broad, designed their lenses to be more neutral.
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Modern Voighlander Heliar lenses bear little to zero rendition resemblance to lenses made for large format film in the early to mid 20th century. Which is to say, be careful of thinking naming conventions will render a scene similarly across the ages. Another example of what i mean is anything labeled “Sonnar.” How well a lens is corrected is more a function of careful design. Don’t believe me? Compare early Zeiss, mid-century Soviet, and the (justifiably) highly regarded 10.5cm/105mm Nikkor-P “Sonnar” designs. Out of focus rendition, chromatic aberration, flare, and astigmatism are treated widely differently depending on who designed the lens and is not something inherent in the basic optical layout. The Kingslake comments previously noted elsewhere in this thread about the Tessar formula being another excellent example. I’ve not encountered such a consistently horrid lens (and I’ve owned far too many of them) as the Zeiss 50mm f/3.5 or f/2.8 Tessar coming from the former Eastern Bloc. They blew it. It never gets “sharp”, really. f/8 seems the best it can do for an acceptable image.
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Modern optics can suffer from a surprising level of field distortion (barrel or pincushion). It appears to me that lens designers sometimes rely rather strongly on software to correct this kind of distortion since it makes it easier/cheaper to correct for chromatic aberration, astigmatism, and flare. In general, vintage lenses can be surprisingly “rectilinear” and I’ve not found it necessary to lean heavily on distortion corrections.
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Many vintage and most modern optics appear to offer pretty good field flatness. Zoom lenses can be another matter, particularly those designed for SLR and early DSLR. No, not all suffer from this, but I can pretty much find a weak spot in just about any zoom. There’s nearly always a “hole” somewhere in the zoom range, or so it seems.
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Even knowing all these things, trying to see an advantage of one thing over another can be difficult. I would enjoy buying a beer for the person who could sit down next to me and tell me which image was made with which lens. It’s impossible, of course. But because we’re on the “inside” and it matters to us, we often place a LOT of emphasis on the lenses we choose. I can’t tell the difference between images made with a new Sigma 24mm f/3.5 DG DN and an early '80’s Nikon Nikkor 24mm f/2.8 Ai. I could say similar things about just any of the lenses I own, vintage or modern.
So after all these years and all this thrashing and whinging and wrangling where did I find the “magic” I was looking for? I found it in careful image processing. This means tightly controlled color management, color grading, sharpness and local contrast controls, etc, etc, etc. This means being clear with myself on what I seek in and how to express a subject/scene in the final result.
OK. Enough of that. There’s much more I could say, but why? I’ve already said too much.
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Exactly this!
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Many vintage or modern primes are exceptions, see counterexamples here. Eg the Voigtlander Nokton 35mm F1.2 in the examples is particularly wavy. (Which, BTW, is totally fine once the user knows about it and is willing to compensate or exploit the effect).
Frankly, I wish manufacturers made some modern glass with significant and interesting field curvature, especially wide open. It allows for interesting compositions, like tilt shift lenses. But all reviews these days start with photographing a flat surface and discussing how sharp the corners are.
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Regarding Is m43 flat? The side by side comparisons feat. the Lumix GX8 — YANNICK KHONG :
I can see a clear difference in some of the image-pairs. For example, in https://images.squarespace-cdn.com/content/v1/521bb60ae4b03dae28cdf4bc/1447485692185-0EOC4X5OQYEMCKUH2OTN/image-asset.jpeg?format=2500w the “Libre Arts” text is more legible in the left image.
I’m not convinced the results support the conclusion that:
the more glass elements a lens has, the flatter the perspective and depth will become.
(Nor do I much care.)
I do agree that:
If you don’t see the differences, simply disregard this article and be happy using whatever you are using.
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