Okay, for the benefit of all, I have now uploaded the quick optical vignetting test I did when I had both the Summicron Asph II and Ultron II (both with my Z6UT). Click the link below to see.
I have cropped out the halogen spots that are the interesting parts of the two images. Focus is set at 70cm and the row of spots is about 4 meters away. Both lenses are shot wide open. From this test, it is quite apparent that the Ultron II has markedly more truncation of bokeh balls. This is the same as saying it has more optical vignetting.
The difference in illumination isn't as dramatic as the truncation should imply, which suggests that the Ultron II may have a longer exit pupil than the Summicron. (A longer exit pupil will reduce natural and pixel vignetting.)
LarsHP wrote:
You are either misreading or misunderstanding.
As you can see from the link I provided above, the vignetting test with the Summicron and Ultron were done on the same camera, my Z6UT. That means apples to apples and proves my point, yes.
(I have also done some optical vignetting tests that support this point, but haven't posted those.)
My point you are quoting here refers to why Bastians test shows less vignetting than my test WITH THE SAME LENS, namely the Ultron II. So, the difference in illumination between the M10 and Z6UT is sensor related (caused by the micro lenses). That explains why we can't compare his and my vignetting images.
EDIT: In the YouTube review Benj Haisch did, it is also quite evident that the bokeh balls (in the bushes) from the Ultron II are clearly oval-shaped already in the mid-frame which isn't the case with his Summicron Asph II. This is consistent with what I am saying.
Yes, I did misunderstand what you were saying, but that is my fault. But I still don't think you tests "prove" anything or come close to proving it. They show with that camera (Z6 UT) slightly less vignetting for the summicron than the Voigtlander which in no way support your rather large claim that the Voigtlander is not at all useful at f/2 over f/2.4 while the summicron is. That is just way too big of claim to be supported by one test that shows minimal differences, IMO, from a camera that is not even designed to use the lenses.
LarsHP wrote:
Okay, for the benefit of all, I have now uploaded the quick optical vignetting test I did when I had both the Summicron Asph II and Ultron II (both with my Z6UT). Click the link below to see.
I have cropped out the halogen spots that are the interesting parts of the two images. Focus is set at 70cm and the row of spots is about 4 meters away. Both lenses are shot wide open. From this test, it is quite apparent that the Ultron II has markedly more truncation of bokeh balls. This is the same as saying it has more optical vignetting.
The difference in illumination isn't as dramatic as the truncation should imply, which suggests that the Ultron II may have a longer exit pupil than the Summicron. (A longer exit pupil will reduce natural and pixel vignetting.)
Again, there is a difference here between these two lenses, but I don't see a huge difference. They both show a lot of vignetting. The Voigtlander shows more, but I don't see a night and day difference. Whether this difference, which I would label small. is enough to bother a particular person is a subjective judgment. I does not bother me, but YMMV. What I object to is the claim that this in my view small difference is enough to characterize for all of us the Voigtlander unusable at f/2 and the summicron perfectly fine. It isn't that way to me. I find the differences small and I find both lenses have a lot of vignetting. If I cared a lot about vignetting such that this in my view small differences was fundamental in selecting a lens then I would be looking at other lenses with a lot less vignetting (they exist), but again YMMV.
If you take your M10 with 28mm Ultron II, focus at infinity, take a picture of something very evenly lit like the sky at f/2 and f/2.4, with ISO and shutter fixed, then you can see that only a spot in the center is affected. The sides are not affected at all.
When I did this with the Summicron Asph II, the sides clearly gets darker. This means it's f/2 aperture is affecting most of the frame, while in the Ultron II only a "hot spot" in the center is f/2.
Sep 20, 2022 at 12:26 PM
Steve Spencer Offline • • • • • • • Upload & Sell: On
LarsHP wrote:
If you take your M10 with 28mm Ultron II, focus at infinity, take a picture of something very evenly lit like the sky at f/2 and f/2.4, with ISO and shutter fixed, then you can see that only a spot in the center is affected. The sides are not affected at all.
When I did this with the Summicron Asph II, the sides clearly gets darker. This means it's f/2 aperture is affecting most of the frame, while in the Ultron II only a "hot spot" in the center is f/2.
I have done exactly that and if you are careful not to blow out either shot, the short side on my camera and lens is affected all the way to the edge and in my view that does not make a small center spot. It is a very large center spot. My experience is different from what you are reporting and that is why I have repeatedly reported my experience. It is not consistent with yours and you keep reporting your experience not as your experience but as fact.
It is a fact on my camera which, granted, isn't a Leica M camera, but a Kolari Vision Ultra Thin converted camera.
I am referring to the edge of the long side, which isn't affected at all in the Ultron, but clearly is in the Summicron. On the short side, there is a faint difference between f/2 and f/2.4 in the Ultron, while there is an obvious difference in the Summicron.
However, the optical vignetting appears to be the same in Bastian Kratzkes test as in mine, which perhaps is the most important, since that can't be fixed in post, and that definitely is visible already on the short side. Benj Haischs tests clearly shows that too.
Steve Spencer wrote:
I have done exactly that and if you are careful not to blow out either shot, the short side on my camera and lens is affected all the way to the edge and in my view that does not make a small center spot. It is a very large center spot. My experience is different from what you are reporting and that is why I have repeatedly reported my experience. It is not consistent with yours and you keep reporting your experience not as your experience but as fact.
Sep 20, 2022 at 01:15 PM
Steve Spencer Offline • • • • • • • Upload & Sell: On
LarsHP wrote:
It is a fact on my camera which, granted, isn't a Leica M camera, but a Kolari Vision Ultra Thin converted camera.
I am referring to the edge of the long side, which isn't affected at all in the Ultron, but clearly is in the Summicron. On the short side, there is a faint difference between f/2 and f/2.4 in the Ultron, while there is an obvious difference in the Summicron.
However, the optical vignetting appears to be the same in Bastian Kratzkes test as in mine, which perhaps is the most important, since that can't be fixed in post, and that definitely is visible already on the short side. Benj Haischs tests clearly shows that too.
It is an observation on your camera or one piece of data. Data are not to be equated with facts. Facts are more abstract truths than individual observations. Colloquially someone might say it is a fact I saw X, but everyone really knows what that means and it is that the person is saying they really saw it and nothing more. If all you are claiming is your own observations that is fine, but the way you are phrasing it appears to be a more abstract and general claim and that you have no evidence for.
The optical vignetting is an important issue and that is not in dispute, but how much that bothers people is going to be subjective. Both the Voigtlander 28 f/2 II and the Leica Summicron 28 Asph have a ton of optical vignetting as almost all rangefinder lenses do. No one is questioning that. What I am disputing is that there is a huge difference between these lenses. I don't see that at least from my point of view. If you can't live with truncated bokeh balls (or bokeh that can get swirly sometimes), then neither is going to meet your requirements. If you can live with these deficiencies, perhaps because you think the small lenses are worth it, then in my view the differences are minimal, but you can certainly feel differently about that and probably do. Just don't portray it as a fact, that the Voigtlander is much worse than the Summicron. That is a subjective assessment, one you are free to hold but not one you can or should claim others must hold.
The Voigtlander wins in terms of resolution/contrast at center but in regards to optical vignetting I would give the advantage to the Leica but it's not a big difference, only noticeable by the cats eye shape's specular highlights on the Voigt.
Both lenses have pleasant rendering to my taste. The Voigtlander's transition is smoother but the difference is small and only noticeable when pixel peeping.
I will find my side by side resolution/rendering comparison and post here soon.
Infinity Performance compared to Leica 28mm f/2 Summicron (Version II)
I will be comparing the Voigtlander 28/2 Ultron II vs Leica 28mm f/2 Summicron (Version II). The latter is famous for its excellent resolution and contrast performance and many landscape photographers love this lens. In terms of resolution and contrast, the Voigtlander actually outperforms the Leica at center and extreme corners. Both lenses have low field curvature.
Distance: Infinity
Focus: Center - Best of three @ 12.4x magnification
Software: Lightroom with FM Default Landscape Sharpening. All other settings set to default
PS: Vignetting and distortion were NOT corrected for both lenses.
28mm CENTER resolution/contrast comparison between Voigtlander 28/2 Ultron II and Leica 28mm f/2 Summicron (Version II)
f/2: The Voigtlander 28/2 II performs noticeably better wide open at center
f/2.8: Both lenses improve but the Voigtlander still outperforms the Leica in terms of resolution and contrast. This seems to be the optimal aperture for the Voigtlander
f/4: Similar performance here. The Voigtlander is still slightly ahead. This is the optimal aperture for the Leica
f/5.6: Similar performance
f/8: Diffraction is now more visible and they perform similarly.
Rendering compared to to Leica 28mm f/2 Summicron (Version II)
All samples shot wide open.
The Voigtlander 28/2 II yields higher contrast and slight higher resolution at the focused area. Transition zone is smoother for the Voigtlander while the Leica shows less optical vignetting (rounder specular highlights off-axis)
Both lenses seem to perform similarly in regards to flare.
I consider both lenses outstanding for applications that require high resolution/contrast throughout the image field. For the price difference, I recommend the Voigtlander 28mm f/2 Ultron II.
Thanks for these. I think the Voigtlander OOF in these shots generally looks better since my preference is for smoothness of the bokeh shapes over them being more circular. Really a trade off since the Voigtlander has more swirl, so some scenes look more calm with the Cron if you don't look closely enough to be distracted by the onion ring bokeh.
Here we are going into what words we use, not so much what we see, I think. The reason why I say "fact" is that you previously said my findings are subjective, which isn't true. Does the Ultron II have more optical vignetting than the Summicron Asph II? Yes, and that's not subjective, which means it's a "fact" (as opposed to subjective*). We can see that in the test I just shared, in the test Benj Haisch did on YouTube, and now in the tests Fred Miranda just shared.
The illumination difference isn't huge, we agree on that, but we are discussing the impact of half a stop, which in itself isn't much. So, from that point of view, and that of the truncation of bokeh balls in the mid-frame and further away from the center, there is an obvious difference - again, considering that we are talking about how much impact half a stop makes.
* It appears that you describe the word "fact" in the way scientific papers use it. That's not how I use it. I use it as opposed to subjective.
Steve Spencer wrote:
It is an observation on your camera or one piece of data. Data are not to be equated with facts. Facts are more abstract truths than individual observations. Colloquially someone might say it is a fact I saw X, but everyone really knows what that means and it is that the person is saying they really saw it and nothing more. If all you are claiming is your own observations that is fine, but the way you are phrasing it appears to be a more abstract and general claim and that you have no evidence for.
The optical vignetting is an important issue and that is not in dispute, but how much that bothers people is going to be subjective. Both the Voigtlander 28 f/2 II and the Leica Summicron 28 Asph have a ton of optical vignetting as almost all rangefinder lenses do. No one is questioning that. What I am disputing is that there is a huge difference between these lenses. I don't see that at least from my point of view. If you can't live with truncated bokeh balls (or bokeh that can get swirly sometimes), then neither is going to meet your requirements. If you can live with these deficiencies, perhaps because you think the small lenses are worth it, then in my view the differences are minimal, but you can certainly feel differently about that and probably do. Just don't portray it as a fact, that the Voigtlander is much worse than the Summicron. That is a subjective assessment, one you are free to hold but not one you can or should claim others must hold....Show more →
Sep 21, 2022 at 04:51 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
LarsHP wrote:
Here we are going into what words we use, not so much what we see, I think. The reason why I say "fact" is that you previously said my findings are subjective, which isn't true. Does the Ultron II have more optical vignetting than the Summicron Asph II? Yes, and that's not subjective, which means it's a "fact" (as opposed to subjective*). We can see that in the test I just shared, in the test Benj Haisch did on YouTube, and now in the tests Fred Miranda just shared.
The illumination difference isn't huge, we agree on that, but we are discussing the impact of half a stop, which in itself isn't much. So, from that point of view, and that of the truncation of bokeh balls in the mid-frame and further away from the center, there is an obvious difference - again, considering that we are talking about how much impact half a stop makes.
* It appears that you describe the word "fact" in the way scientific papers use it. That's not how I use it. I use it as opposed to subjective.
I think the word you want instead of fact is objective. The opposite of subjective is objective. I agree and have agreed all along that there is an objective difference between the vignetting of the Voigtlander 28 f/2 II and the Leica 28 Summicron. What is in dispute is the meaning of that objective difference. Is it a small difference and not that consequential as I believe (and as I think Fred suggests above) or is it a large difference that is a major defect in the Vogitlander but totally acceptable for the Summicron (as I think you have been suggesting). It is that meaning of the objective difference that is a very subjective judgment and a judgment on which we can and should be able to disagree. Our mileage may very well vary precisely because the meaning of that objective judgment is very much a subjective one.
You are still discussing the words I use, not what I mean. What I have tried to convey in my later posts, but to you obviously not succeeded with until recently(?), is that the degree of optical vignetting isn't an opinion or a point of view, but something physical, something you can measure. Whether I call that factual, objective or measurable should be of no consequence for readers of this thread IMO. In other words, the point I have been making is and was that the difference in optical vignetting is not a personal viewpoint or opinion, but something relating to the optical features of the Ultron II lens. Did I make myself clear now?
My point of view is that the optical vignetting behaves so sharply in the central part of the frame, that the usefulness of the f/2 aperture is quite limited since it doesn't affect the image much except for the very center*. With the Summicron, the f/2 aperture is covering the whole central part of the frame, which makes it much more useful.
That's a new way of saying what I have tried to say in the last several posts (as well as much earlier in this thread).
* On my Z6UT, the edge of the short side barely show an exposure difference between f/2 and f/2.4, but as I understand it, you see more difference on your M10. Bokeh balls are more revealing there, and those will be the same on a Leica M camera.
Steve Spencer wrote:
Hi Lars,
I think the word you want instead of fact is objective. The opposite of subjective is objective. I agree and have agreed all along that there is an objective difference between the vignetting of the Voigtlander 28 f/2 II and the Leica 28 Summicron. What is in dispute is the meaning of that objective difference. Is it a small difference and not that consequential as I believe (and as I think Fred suggests above) or is it a large difference that is a major defect in the Vogitlander but totally acceptable for the Summicron (as I think you have been suggesting). It is that meaning of the objective difference that is a very subjective judgment and a judgment on which we can and should be able to disagree. Our mileage may very well vary precisely because the meaning of that objective judgment is very much a subjective one. ...Show more →
Sep 21, 2022 at 09:08 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
LarsHP wrote:
You are still discussing the words I use, not what I mean. What I have tried to convey in my later posts, but to you obviously not succeeded with until recently(?), is that the degree of optical vignetting isn't an opinion or a point of view, but something physical, something you can measure. Whether I call that factual, objective or measurable should be of no consequence for readers of this thread IMO. In other words, the point I have been making is and was that the difference in optical vignetting is not a personal viewpoint or opinion, but something relating to the optical features of the Ultron II lens. Did I make myself clear now?
My point of view is that the optical vignetting behaves so sharply in the central part of the frame, that the usefulness of the f/2 aperture is quite limited since it doesn't affect the image much except for the very center*. With the Summicron, the f/2 aperture is covering the whole central part of the frame, which makes it much more useful.
That's a new way of saying what I have tried to say in the last several posts (as well as much earlier in this thread).
* On my Z6UT, the edge of the short side barely show an exposure difference between f/2 and f/2.4, but as I understand it, you see more difference on your M10. Bokeh balls are more revealing there, and those will be the same on a Leica M camera.
Yes, I got all of that, but what I added is your point of view is subjective and I disagree sharply with your point of view. We should feel free to agree to disagree about that, however, as that point of view is very much a subjective matter. I also wanted to point out that objectively on my M10 the difference between f/2 and f/2.4 is plenty noticeable for about a 24mm image circle in the center of the frame. Subjectively, I do not consider that size of image circle as small. It is quite large from my subjective view. I am not sure what your subjective view is of that size of image circle. Maybe you agree that is quite large, but maybe you still see that as small.
Anyone's point of view is per definition subjective. Why do you need to point that out? It only emphasizes that you disagree, while trying to make your point of view more correct.
The illumination will be better in an M camera than my Z6UT because there is less pixel vignetting, and from that point of view I understand your stance. However, optical vignetting will be the same, as seen in the side by side tests from Benj Haisch, Fred Miranda and me. These tests show obviously oval shaped bokeh balls already within the mid-frame (less than 10mm from the center) where the Summicron balls still look circular. That is making my point well and needs no further support. Different people will value that truncation differently.
We have made our stances clear repeatedly, so I don't see any reason to continue.
Steve Spencer wrote:
Yes, I got all of that, but what I added is your point of view is subjective and I disagree sharply with your point of view. We should feel free to agree to disagree about that, however, as that point of view is very much a subjective matter. I also wanted to point out that objectively on my M10 the difference between f/2 and f/2.4 is plenty noticeable for about a 24mm image circle in the center of the frame. Subjectively, I do not consider that size of image circle as small. It is quite large from my subjective view. I am not sure what your subjective view is of that size of image circle. Maybe you agree that is quite large, but maybe you still see that as small. ...Show more →
