I am not referring to LoCA only. I didn't (and don't) like the oof rendition too.
From what I've seen, the oof rendition of both the 28/2 Apo and Simera 28/1.4 is preferable. And both don't suffer from LoCA.
'even very inexpensive, small, and lightweight AF lenses from China sometimes deliver almost apochromatic results in this regard.'
The standards for CA are now very high across the board. Very few of the Chinese lenses ever claimed APO status, however, or ever made a thing of it - they will leave that to the Europeans. The only mention in Thypoch's long 28/1.4 web page is this: 'precise chromatic control', the other lenses gets simiiar brief treatment. Vanishingly small CA seems good enough. Viltrox's web page does not even mention color correction, it's now taken as a given.
I strongly believe lens design is about compromises. One can design the lens to be as perfect as possible but will somehow take away some other qualities that's not readily visible. To me a perfect lens is one with all qualities I desire and with compromises I can accept. I was reminded of the 40/1.2, where almost any high contrast outlines will trigger the purple fringing. It didn't occur to me of being a problem when I had it, but I have a very different workflow now so I would avoid one that's guarantee to see strong purple fringing wide open, that's why I've not been considering this 28mm Nokton for the longest time.
philip_pj wrote:
'even very inexpensive, small, and lightweight AF lenses from China sometimes deliver almost apochromatic results in this regard.'
The standards for CA are now very high across the board. Very few of the Chinese lenses ever claimed APO status, however, or ever made a thing of it - they will leave that to the Europeans. The only mention in Thypoch's long 28/1.4 web page is this: 'precise chromatic control', the other lenses gets simiiar brief treatment. Vanishingly small CA seems good enough. Viltrox's web page does not even mention color correction, it's now taken as a given.
I have to say, the Simera 28/1.4 handles axial CA and purple fringing remarkably well. In my review I pointed out how impressive that is, especially when you line it up against other fast 28s like the Leica Summilux or the Voigtlander Nokton. Of course, there are tradeoffs. When a design pushes hard in one direction, something else usually gives a little. The Leica and Voigtlander both deliver higher contrast, which makes subjects pop more, and their rendering has a different character. Still, I am glad the Simera exists. It brings its own look to the table and its own philosophy of where to apply the corrections, and plenty of photographers will prefer that balance.
Infinite Quid Pro Quo ... the essence of optical design. Now you're cooking with glass ... each designer makes his choices, and along with that comes the array of variance.
Sometimes it is easier to "choose your poison(s)" by know what you don't like (e.g. purple fringing, distortion, etc.), than worrying which is better / worse for a given thing. Kinda depends on whether you're looking for utilitarian vs. specialization, too.
Noodling through all that it takes to land the math and achieve the look ... in the balance as desired can be done simply, and incorporate more issues, or it can ultra-complex and minimize toward fewer issues, or it can lean into a given attribute to maximize it (quid pro quo to something else).
Yup ... quid pro quo ... always.
Optics design is a craft ... with as many variations as craft beer. And, as many variations in personal temperament / taste to go with it.
Is anyone able/willing to share a raw file from the native Sony lens which has significant LOCA or purple fringeing in it so that I can see how well my preferred raw tools deal with it? I am thinking of buying and I think I would like the 1.5 Nokton over the incoming f2 Lanthar for the extra speed as I shoot in low light, so I am interested to see how easily I can deal with any fringeing issues on high contrast edges
Don't shoot me for asking but have any Sony shooters compared this lens to the Viltrox 28mm 1.8 lens ? The Voigtlander is MF and the Viltrox AF I know, and I would hope that the Voigt is a lot nicer in terms of rendering
Likely very similar to the M mount lens is this regard. It's really easily corrected thanks to the high contrast of the lens.
Hawkmoon wrote:
Is anyone able/willing to share a raw file from the native Sony lens which has significant LOCA or purple fringeing in it so that I can see how well my preferred raw tools deal with it? I am thinking of buying and I think I would like the 1.5 Nokton over the incoming f2 Lanthar for the extra speed as I shoot in low light, so I am interested to see how easily I can deal with any fringeing issues on high contrast edges
Hawkmoon wrote:
Is anyone able/willing to share a raw file from the native Sony lens which has significant LOCA or purple fringeing in it so that I can see how well my preferred raw tools deal with it? I am thinking of buying and I think I would like the 1.5 Nokton over the incoming f2 Lanthar for the extra speed as I shoot in low light, so I am interested to see how easily I can deal with any fringeing issues on high contrast edges
Choose your poison ...
f/1.5 + aberration
f/2 + ISO
Imo, in today's realm of what 1 stop (slightly under in this case) of ISO brings to the table ... is the faster Nokton really requisite for dealing with low light (i.e. extra speed). If we were talking about 1.5 vs. 2.8 or 3.5 for the smaller lens options, then 2 or three stops of ISO would be significantly different. But, when the diff is only one stop ... the matter of whether the LOCA / fringing is "significant" vs. the amount of significance one stop of ISO brings to the table might be worth a re-consideration.
That said, I recognize this is a 3-way comp fo the Sony vs. both Voigts, so it is degrees of relative comparison, coming from your baseline wrt the Sony.
As to the Nokton vs. the Lanthar ... tough call, as I can see either of them in my bag. But, (imo) the difference of f/1.5 vs. f/2 isn't that much of a differentiator for me. It's more a matter of drawing style difference, haptic, size, etc. For less than one stop diff, the f/1.5 vs. f/2 is not that significant an issue to me in terms of light gathering. Shooting chrome film ... then, maybe. Digital, not so much.
Imo, in today's realm of what 1 stop (slightly under in this case) of ISO brings to the table ... is the faster Nokton really requisite for dealing with low light (i.e. extra speed). If we were talking about 1.5 vs. 2.8 or 3.5 for the smaller lens options, then 2 or three stops of ISO would be significantly different. But, when the diff is only one stop ... the matter of whether the LOCA / fringing is "significant" vs. the amount of significance one stop of ISO brings to the table might be worth a re-consideration.
That said, I recognize this is a 3-way comp fo the Sony vs. both Voigts, so it is degrees of relative comparison, coming from your baseline wrt the Sony.
As to the Nokton vs. the Lanthar ... tough call, as I can see either of them in my bag. But, (imo) the difference of f/1.5 vs. f/2 isn't that much of a differentiator for me. It's more a matter of drawing style difference, haptic, size, etc. For less than one stop diff, the f/1.5 vs. f/2 is not that significant an issue to me in terms of light gathering. Shooting chrome film ... then, maybe. Digital, not so much.
I would concur with this. The draw is very different between the Noktons (particularly the more compact, character-oriented ones) and the APO-LANTHAR series, I'd say that's the main differentiator, the light gathering being a far-flung consideration.
From my perspective, versus something like the 28mm ƒ/2.0 APO-LANTHAR, a significant rendering difference is that the Nokton has a smoother, slower transition zone from in to out of focus.
The quicker focus dropoff of the LANTHAR lenses means that from a visual perspective, even the slower lens can sometimes look similarly defocused when viewed near a subject, accepting that far-away bokeh balls will be slightly larger on the Nokton. However, that fast dropoff rendering is occasionally less desirable for certain types of shots (and the same for the Nokton, occasionally its slower transition leads to less apparent subject separation). I would certainly be happy to own both.
Stargenx wrote:
From my perspective, versus something like the 28mm ƒ/2.0 APO-LANTHAR, a significant rendering difference is that the Nokton has a smoother, slower transition zone from in to out of focus.
Could you please provide reliable examples to support this statement?
I have both the 35/2 AL and the 50/2 AL with Z mount. I haven't been able to use the Z CV 28/2 Apo yet because it won't be available until January. However, I did purchase (and use) the 28/1.5 Nokton, but I returned it because I didn't like its rendering. I have never noticed a “softer and more gradual transition zone from focus to blur.” I am familiar with this type of performance, which is typical of several Zeiss ZF.2 lenses. And I have never noticed that the 28/1.5 has a softer and more gradual transition than my Apo-Lanthars. The 50/2 is almost perfect; the 35/2 AL has a rather structured bokeh on several occasions and is not as good. Bokeh has no relationship with transitions from the plane of focus to oof planes though.
Can any owners of the Sony version of the 28 1.5 Nokton comment on whether there is a third party square metal hood that fits it? I can see one by Laoge for the Leica versions but not the e-mount
Nov 24, 2025 at 05:47 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
Ripolini wrote:
Could you please provide reliable examples to support this statement?
I have both the 35/2 AL and the 50/2 AL with Z mount. I haven't been able to use the Z CV 28/2 Apo yet because it won't be available until January. However, I did purchase (and use) the 28/1.5 Nokton, but I returned it because I didn't like its rendering. I have never noticed a “softer and more gradual transition zone from focus to blur.” I am familiar with this type of performance, which is typical of several Zeiss ZF.2 lenses. And I have never noticed that the 28/1.5 has a softer and more gradual transition than my Apo-Lanthars. The 50/2 is almost perfect; the 35/2 AL has a rather structured bokeh on several occasions and is not as good. Bokeh has no relationship with transitions from the plane of focus to oof planes though. ...Show more →
I believe that spherical aberrations make the focus transition between in focus and out of focus longer. Peter Karbe has discussed this in comparing the Leica SL APO lenses and claims that because they have such well corrected spherical aberrations they have a faster transition from in focus to out of focus that is similar to f/1.4 lenses with more aberrations.
I do have the CV 28 f/1.5 Nokton for Sony E mount and it does have quite noticeable spherical aberrations wide open, but these reduce quite a bit by f/2 and even more so by f/2.8. Of course f/1.5 is going to have a faster transition from in focus to out of focus than f/2, and I doubt very much the better correction of spherical aberrations in the 28 f/2 APO is going to make up for that difference in aperture, so comparing the lenses wide open I would expect the Nokton to have the faster transition zone. At f/2 that APO lens might have a faster transition, but the Nokton already has reduced spherical aberrations quite a bit by f/2 so I am not at all sure there will be much of a difference. I suspect it will be hard to tell the difference in the transition zone between these lenses when shot at the same aperture, but I don't have the APO version yet to compare. I suspect the big difference will be in axial CA and in how structured the bokeh is (and likely in field curvature as well), but not in the transition zone. I do plan to have both lenses before long and will try to do a comparison when I have both lenses in hand.
Good morning Steve.
I don't know if spherical aberrations affect the smoothness of the transition zone from focus to blur in any way.
If I remember correctly, you used the Zeiss 100/2 Makro-Planar, a lens with well-corrected spherical aberration (zero focus shift). Based on your experience, how would you rate its tonal transitions? Abrupt or smooth/gradual?
I'm not sure if you guys are talking about the same thing and apologies if this is a hijack but with the CV APO 50mm f2 vs Nokton 50mm f1.2, at the same aperture, the nokton blurs faster than the apo, the apo is more gradual.
It's like a little under 1 stop difference.
The nokton has lovely fall-off at f1.6 to my eyes at 1-2m. And I also like the apo's more gradual falloff.
It helps give the APO more of a realism vibe (and feeling of a sharp image) at the same aperture, whereas the nokton is more subject focussed and it helps with isolation. You can do both with either to a nice level, perhaps not at all distances though).
-- I still don't get the concept of transition "zone" because at what point is something considered out of focus. It's either in-focus or it's out of focus to varying degrees, or am I wrong there?
Zone sounds to me like the person means to say there's a part where things are "kind of" in focus before they're "fully" out of focus - that seems hard to define, I usually struggle when the reviewers mention it to follow along exactly.
I'm probably being an idiot somehow but I've had this question for months now. Same with the lens markings for something being in-focus at x distance at a certain aperture. They mean perfectly in focus between those distances, or acceptable focus?
Nov 24, 2025 at 09:33 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
Ripolini wrote:
Good morning Steve.
I don't know if spherical aberrations affect the smoothness of the transition zone from focus to blur in any way.
If I remember correctly, you used the Zeiss 100/2 Makro-Planar, a lens with well-corrected spherical aberration (zero focus shift). Based on your experience, how would you rate its tonal transitions? Abrupt or smooth/gradual?
I have used the Zeiss 100 f/2 Makro-Planar a lot. I liked some aspects of that lens a lot and the bokeh was one of the things I liked. I would say it only has moderately low spherical aberrations (SA) at f/2. It does have close to zero focus shift, however, but that is because the spherical aberrations are very well compensated for by its floating element design which keeps the SA fairly low even at close focus.There are a lot of lenses with even lower SA than the Zeiss 100 f/2--the Leica SL APO lenses would definitely be some of them but others including many Sony lenses made in the last decade.
I would rate the transition zone of the Zeiss 100 MP, as smooth but moderate in speed. It is f/2 so that means it is going to be more gradual than lenses with faster apertures, but for an f/2 lens I don't think it is particularly gradual or fast. I used to have the Leica R 80 f/1.4 and at f/2 that had a noticeably more gradual focus transition and lenses like the Leica SL APO lenses would probably have a faster focus transition.
I think, but I am not sure that spherical aberrations make the focus transition slower but the smoothness of the transition is affected by a lot of things and spherical aberrations is just one of them. Shape of the blur disc, which is affected by aperture shape, vignetting, which affects the blur especially towards the edges and corners, and even the type of shutter being used (e.g., it is a known issue that first curtain electronic shutter can affect the smoothness of the blur at high speed) can affect the smoothness of the blur.
Yogifi wrote:
I'm not sure if you guys are talking about the same thing and apologies if this is a hijack but with the CV APO 50mm f2 vs Nokton 50mm f1.2, at the same aperture, the nokton blurs faster than the apo, the apo is more gradual.
It's like a little under 1 stop difference.
The nokton has lovely fall-off at f1.6 to my eyes at 1-2m. And I also like the apo's more gradual falloff.
It helps give the APO more of a realism vibe (and feeling of a sharp image) at the same aperture, whereas the nokton is more subject focussed and it helps with isolation. You can do both with either to a nice level, perhaps not at all distances though).
-- I still don't get the concept of transition "zone" because at what point is something considered out of focus. It's either in-focus or it's out of focus to varying degrees, or am I wrong there?
Zone sounds to me like the person means to say there's a part where things are "kind of" in focus before they're "fully" out of focus - that seems hard to define, I usually struggle when the reviewers mention it to follow along exactly.
I'm probably being an idiot somehow but I've had this question for months now. Same with the lens markings for something being in-focus at x distance at a certain aperture. They mean perfectly in focus between those distances, or acceptable focus?...Show more →
The sharpness of the lens has its influence. A less sharp lens should reproduce a point (0 dimensional) with a larger size both on the focus plane and on out-of-focus planes as well, thus giving rise to more blurred oof subjects. Does this influence the 3D rendering? I'm not so sure.
As you correctly stated, the APO has more realism; i.e., a 3D look closer to reality. Unfortunately, people think that lenses with residual aberrations have a larger 3D pop. This might depend on their assumption that a more pictorial rendering translates into 3D pop. Actually, it's the opposite
Nov 24, 2025 at 09:56 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
Yogifi wrote:
I'm not sure if you guys are talking about the same thing and apologies if this is a hijack but with the CV APO 50mm f2 vs Nokton 50mm f1.2, at the same aperture, the nokton blurs faster than the apo, the apo is more gradual.
It's like a little under 1 stop difference.
The nokton has lovely fall-off at f1.6 to my eyes at 1-2m. And I also like the apo's more gradual falloff.
It helps give the APO more of a realism vibe (and feeling of a sharp image) at the same aperture, whereas the nokton is more subject focussed and it helps with isolation. You can do both with either to a nice level, perhaps not at all distances though).
-- I still don't get the concept of transition "zone" because at what point is something considered out of focus. It's either in-focus or it's out of focus to varying degrees, or am I wrong there?
Zone sounds to me like the person means to say there's a part where things are "kind of" in focus before they're "fully" out of focus - that seems hard to define, I usually struggle when the reviewers mention it to follow along exactly.
I'm probably being an idiot somehow but I've had this question for months now. Same with the lens markings for something being in-focus at x distance at a certain aperture. They mean perfectly in focus between those distances, or acceptable focus?...Show more →
Best focus is always at a very specific distance and as you move away from this distance things become less in focus. Now if a lens doesn't have any field curvature or focus shift (which is just an ideal as all lens have at least a tiny bit of field curvature and focus shift), this distance is a plane (with field curvature it won't be a plane but will be slightly different at different distances). That said, we won't always be able to perceive that very specific distance and as you move away from it we won't see a difference. This perception can be slightly different for different people and certainly depends on magnification of the image. What appears in focus at lower magnification, will be noticeably as less in focus at greater magnification. So whenever we say that a shot is in focus at X distance, we need to know the magnification and viewing conditions.
So, a shot can look totally in focus for lets say 10M from the camera at a smaller magnification/longer viewing distance but if you get closer to the image or magnify the image it can look less in focus. So when the lens marking say in focus for X distance at a certain aperture they are saying where best focus would be if the lens is perfect and has no field curvature or focus shift (no actual lens is perfect, however) and these markings are not very precise. All that is fine and basically works as long as the lens is reasonably good and you don't try to magnify the image too much or view the image too closely. When you do you will see the imprecision in the lens markings and you will see the imperfections of the lens.
You are certainly not at fault whatsoever, for not fully understanding the regions of focus. Very few do, yet we all bandy around the terms as though all others understand perfectly. Did you know there is no useful definition of 'bokeh' as provided by the search engines and AI (it's just 'blur'), no mention of the all-important transition zone?
The degree of sharpness from the focal plane *is a continuum* in real world perception of our images. The focal plane is very narrow at wide apertures, yet you may have 100 metres of content behind the focal point, perhaps some in front as well.
We must be practical. Very little of what we see as 'in-focus content' is truly sharp at wider apertures. It is however regarded as sharp enough to be called 'in-focus'. At some point, as your eye moves axially to objects further from the focal point, the loss of focus is such that we refer to it as 'out-of-focus' (or bokeh).
Because all content in the image immediately off the focal plane moving in an axial direction is not as sharp as the focal plane content, it forms the commencement of the transition zone. Thus the transition zone begins just past the point of best focus (the focal plane).
But where does it end? The exact location of the crossover point from the transition zone to enter the bokeh region (I call this the bokeh field) is ARBITRARY, from a visual perspective (leaving aside controversial formulae using Airy Disks and Circles of Confusion). It's also affected by the drawing styles of lenses in this critical region.
But for each of us, we have our own idea where it is in any image. Because 'bokeh' is defined by its state of blur, some think the onset of bokeh lies at the point where motifs can no longer be readily identified. Others would choose a level of blur they are no longer prepared to call 'in-focus' content.
