You are right that the strong vignetting causes the Ultron II making cats eye bokeh balls. It does so even in the mid-frame where the Summicron Asph II has quite circular bokeh balls. However, the Summicron has some outlining in the bokeh balls (tendency towards bubble bokeh balls) in the mid-frame and in the sides and corners it has clearly more busy bokeh than the Ultron II in the bokeh test images I just linked to near MFD (1 meter). The Ultron II has obvious bokeh ball outlining in the sides of the 100% crop combo image though. In other words, pick your poison (bokeh ball outlining in the mid-frame or sides and corners).
Regarding LoCA and LaCA, my tests show that it's a draw. The harsher bokeh in the Summicron images sometimes makes LoCA look worse and perhaps it may look better in other scenes, but generally my tests show that it's about the same. This includes tests where I slowly unfocus a backlit subject in 200% magnification and see how much green outlining it produces. The in-focus LoCA tests is a draw or in favor of the Ultron II to my eyes.
Wide open the Ultron II is sharper than the Summicron-M Asph II. I mean sharper everywhere in the image. Slightly sharper in the center and much sharper in the sides and corners. (For reference to someone who randomly reach this post, this is with Kolari Vision Ultra Thin modified Nikon Z6.)
The only real image quality issue I have with the Voigtländer is the heavy vignetting and its consequences. Transmission outside the very center is not resembling f/2 (compared to the Summicron) which makes me rather label it as a f/2.4 lens. Shooting in the darkness where high ISO is necessary, the Ultron II will require about two thirds of a stop higher ISO. If we are already pushing things, that might be a noticeable drawback. If we are shooting near base ISO, then of course not much. If we can stop down the lens to f/4 or f/5.6, then the Ultron II actually vignette less, so the vignetting issue is mostly limited to wide open and f/2.4 (even though it vignettes more at f/2.8 than the Summicron).
I can see why someone like Benj Haisch who does wedding photography may choose the Summicron-M Asph II over the Ultron II. This includes the "pro image" to the (potential) customers, that the photographer uses equipment that amateurs can't afford and therefore is assumed to be superior. "It's a real Leica lens!"
Neither lens is perfect, but I am actually stunned by lack of optical performance that I expect from a 5000 USD 28mm f/2 lens. Luckily I bought it used at a good price, so I won't loose money when I sell it. The economics may also be part of the reason why someone who bought the Summicron Asph II new won't buy the Ultron II and sell the Leica lens. The loss of money and "Leica aura" will be too high.
rscheffler wrote:
I think it's really going to depend on image content. The interior comparison has very few areas with OOF specular/pinpoint highlights and thus is difficult to really find differences.
My beef with the Ultron's rendering is less at near MFD but at maybe 2-3m with backgrounds containing a lot of specular light sources. The Ultron's optical vignetting truncates the bokeh balls and results in mild swirling that while not a lot, still feels unsettling for me. I'm sure it affects everyone differently.
In the 100% crop example you can see the Ultron exhibits a bit more purple fringing/LoCA, but whether it's a big deal will again depend on image content and expectations.
Without doubt though, the Ultron is a very strong performer. It has me contemplating downsizing from the Lux and accepting the tradeoffs....Show more →
rscheffler wrote:
I think it's really going to depend on image content. The interior comparison has very few areas with OOF specular/pinpoint highlights and thus is difficult to really find differences.
My beef with the Ultron's rendering is less at near MFD but at maybe 2-3m with backgrounds containing a lot of specular light sources. The Ultron's optical vignetting truncates the bokeh balls and results in mild swirling that while not a lot, still feels unsettling for me. I'm sure it affects everyone differently.
In the 100% crop example you can see the Ultron exhibits a bit more purple fringing/LoCA, but whether it's a big deal will again depend on image content and expectations.
Without doubt though, the Ultron is a very strong performer. It has me contemplating downsizing from the Lux and accepting the tradeoffs....Show more →
When comparing Leica and Voigtlander lenses with similar FL and aperture, generally, the former always comes ahead in regards to optical vignetting. Higher optical vignetting does not only means more prominent cats-eye shape, but also uneven OOF rendering where the corners appear sharper than center. It's an ill-effect or 'character' I also dislike.
After re-checking the latest images I linked to, it appears that the bokeh behavior in the sides varies a bit in both lenses. The edge bokeh from the Summicron looks smoother at about 3 meter (10 feet) focus distance, but is more nervous (check the heart, flower and pot in the window) in the image focused @ 1 meter than the Ultron. The Summicron has less bokeh fringing at the edge of the image focused @ 3 meters. In the center, I don't see any CA difference, neither in nor out of focus, but the Ultron has smoother bokeh there (particularly check the wires that holds the flower pot in the veranda).
Fred Miranda wrote:
When comparing Leica and Voigtlander lenses with similar FL and aperture, generally, the former always comes ahead in regards to optical vignetting. Higher optical vignetting does not only means more prominent cats-eye shape, but also uneven OOF rendering where the corners appear sharper than center. It's an ill-effect or 'character' I also dislike.
But don’t we also see sharper corners at wider apertures with the recent CVs that have more vignetting than the Leicas?
Despite some of the drawbacks you mention to the higher vignetting of the CVs, I find that for their f2 lenses, that vignetting gives the images a very nice central subject isolation, which combined with f2 sharpness is really nice. For example, I like my 50 Lux a lot at f/1.4 for subject isolation, but at f/2, I prefer the CV 50 APO since it gives me f/1.4 vignetting plus APO sharpness. Basically the CV tendency toward more vignetting gives me another look I wouldn’t have otherwise.
highdesertmesa wrote:
But don’t we also see sharper corners at wider apertures with the recent CVs that have more vignetting than the Leicas?
I'm not sure if achieving sharper corners is related to optical vignetting. I think the latter has more to do with element(s) diameter, barrel length and entrance pupil. It think that sharper corners is more of a function of number of elements (better correction), glass tech and optical design.
Despite some of the drawbacks you mention to the higher vignetting of the CVs, I find that for their f2 lenses, that vignetting gives the images a very nice central subject isolation, which combined with f2 sharpness is really nice. For example, I like my 50 Lux a lot at f/1.4 for subject isolation, but at f/2, I prefer the CV 50 APO since it gives me f/1.4 vignetting plus APO sharpness. Basically the CV tendency toward more vignetting gives me another look I wouldn’t have otherwise.
Light fall-off towards the corners does not bother me and it's correctable only causing DR decrease and more noise off-axis. What I was referred to is "optical" vignetting that causes uneven rendering and cats-eye shape for the highlights. That's where Leica lenses usually have the upper hand. I only assuming they pay more attention to it.
Fred Miranda wrote:
I'm not sure if achieving sharper corners is related to optical vignetting. I think the latter has more to do with element(s) diameter, barrel length and entrance pupil. It think that sharper corners is more of a function of number of elements (better correction), glass tech and optical design.
Light fall-off towards the corners does not bother me and it's correctable only causing DR decrease and more noise off-axis. What I was referred to is "optical" vignetting that causes uneven rendering and cats-eye shape for the highlights. That's where Leica lenses usually have the upper hand. I only assuming they pay more attention to it.
Gotcha. I recently bought a nearly-new 28 Summicron-M (Safari) and like it very much, more than I thought I would. Perhaps what you mention above is part of why the images look so nice to me.
In some important aspects (such as sharpness) the 28mm Ultron II is superior and others (like bokeh) it's just different. The only point where the Leica is clearly better is regarding vignetting. And frankly, I greatly prefer the look of the Summicron too, but optical performance is the most important feature to me (within the size limits of M mount lenses).
Would I have considered the Ultron if it was labeled as an f/2.4 lens (which it mostly behaves as at medium to long focus distances)? Perhaps not, but after having the two lenses side by side side for a while, I find the Summicron to be much more finicky in order to aquire proper center focus and the sides are clearly behind the Ultron when both are shot at f/2.4. If I was primarily shooting groups of people with my 28mm lens, I might prefer the Summicron, but that's not the case.
From a value for money point of view, the new 28mm Ultron is stunning.
I just slight edit some exposure to match between shots
I have to do some more test at f2 and focus at infinity, the image seems unsharp maybe because focus point was closer than infinity
Thanks for sharing. It's a gem of a lens for UT sensor glass converted and M cameras.
I do see some reverse field curvature in the image of the iron pole and the image with the "cars"-sign to the right.
Bokeh in the sides also seem to be more nervous than I see with my UT modded camera, but this is of course not a side by side situation, so this may be depending on focus distance, subject distance etc.
al404 wrote:
Finally tested on Sony A7C, EXIF report A7iii because I need to fake them otherwise CaptureOne 20 doesn't show up A7C RAW
I just slight edit some exposure to match between shots
I have to do some more test at f2 and focus at infinity, the image seems unsharp maybe because focus point was closer than infinity
Fred Miranda wrote:
When comparing Leica and Voigtlander lenses with similar FL and aperture, generally, the former always comes ahead in regards to optical vignetting. Higher optical vignetting does not only means more prominent cats-eye shape, but also uneven OOF rendering where the corners appear sharper than center. It's an ill-effect or 'character' I also dislike.
highdesertmesa wrote:
But don’t we also see sharper corners at wider apertures with the recent CVs that have more vignetting than the Leicas?
Despite some of the drawbacks you mention to the higher vignetting of the CVs, I find that for their f2 lenses, that vignetting gives the images a very nice central subject isolation, which combined with f2 sharpness is really nice. For example, I like my 50 Lux a lot at f/1.4 for subject isolation, but at f/2, I prefer the CV 50 APO since it gives me f/1.4 vignetting plus APO sharpness. Basically the CV tendency toward more vignetting gives me another look I wouldn’t have otherwise. ...Show more →
Just to further elaborate on what Fred wrote: a consequence of the higher peripheral optical vignetting is that it effectively acts like a smaller aperture opening with the resulting DoF consequences. The 'sharpness' Fred meant, by my reading, is an increase in image content definition - less blur - in the periphery than in the center of the image. This results in an uneven across-frame rendering quality. Sometimes this combines with field curvature away from the camera in the image periphery, which further exaggerates the effect, sometimes to the point where distant OOF objects in image corners are noticeably more defined/in focus than OOF objects of a similar distance in the image center.
rscheffler wrote:
Just to further elaborate on what Fred wrote: a consequence of the higher peripheral optical vignetting is that it effectively acts like a smaller aperture opening with the resulting DoF consequences. The 'sharpness' Fred meant, by my reading, is an increase in image content definition - less blur - in the periphery than in the center of the image. This results in an uneven across-frame rendering quality. Sometimes this combines with field curvature away from the camera in the image periphery, which further exaggerates the effect, sometimes to the point where distant OOF objects in image corners are noticeably more defined/in focus than OOF objects of a similar distance in the image center....Show more →
So if assuming a fairly flat field lens that also has high peripheral optical vignetting (like the RF 50 1.2), can the "DOF consequence" at infinity result in improved corner sharpness?
In the case of 28mm Ultron Asph II versus Summicron Asph II, the Voigtländer lens has a bit of regular field curvature while the Leica has a slight reverse field curvature wide open (but regular stopped down). In practical use, the Ultron has about the same amount of blur in the sides as the 'cron when shot wide open. At short focus distances, the Ultron has more smooth bokeh in the sides and corners, but at medium distances, it's the 'cron that has the upper hand.
rscheffler wrote:
Just to further elaborate on what Fred wrote: a consequence of the higher peripheral optical vignetting is that it effectively acts like a smaller aperture opening with the resulting DoF consequences. The 'sharpness' Fred meant, by my reading, is an increase in image content definition - less blur - in the periphery than in the center of the image. This results in an uneven across-frame rendering quality. Sometimes this combines with field curvature away from the camera in the image periphery, which further exaggerates the effect, sometimes to the point where distant OOF objects in image corners are noticeably more defined/in focus than OOF objects of a similar distance in the image center....Show more →
rscheffler wrote:
Just to further elaborate on what Fred wrote: a consequence of the higher peripheral optical vignetting is that it effectively acts like a smaller aperture opening with the resulting DoF consequences. The 'sharpness' Fred meant, by my reading, is an increase in image content definition - less blur - in the periphery than in the center of the image. This results in an uneven across-frame rendering quality. Sometimes this combines with field curvature away from the camera in the image periphery, which further exaggerates the effect, sometimes to the point where distant OOF objects in image corners are noticeably more defined/in focus than OOF objects of a similar distance in the image center. ...Show more → highdesertmesa wrote:
So if assuming a fairly flat field lens that also has high peripheral optical vignetting (like the RF 50 1.2), can the "DOF consequence" at infinity result in improved corner sharpness?
Good question. I would think it does affect it somewhat, if our theory about optical vignetting increasing peripheral depth of field is correct. But I don't have a way of proving it.
Late to the party and somewhat atypical in my question about this lens...
Has anyone done any shooting on 24mp Sony aps-c with it? Or otherwise care to venture a guess about how it would fare. Would the problematic corner issues at 60mp be mostly washed out by the crop and the lower resolution?
Of course I have read through Fred's review earlier, unfortunately I don't have the experience to extrapolate from that with any certainty to my use case.
Mikey Floyd wrote:
Late to the party and somewhat atypical in my question about this lens...
Has anyone done any shooting on 24mp Sony aps-c with it? Or otherwise care to venture a guess about how it would fare. Would the problematic corner issues at 60mp be mostly washed out by the crop and the lower resolution?
Of course I have read through Fred's review earlier, unfortunately I don't have the experience to extrapolate from that with any certainty to my use case.
I'm using the new Ultron on my Sony A7C quite happily (not APS-C but 24mp) and I think it works pretty well in my actual use. I stop down to f5.6 for "infinity" shots when looking for corner-to-corner sharpness and I'm very happy with the results there. I typically stop my native lenses down to f5.6 or so for similar "infinity" shots as well and there's no special trickery needed with this lens on 24mp in my view. I typically focus somewhere in the midframe rather than dead center though.
Juha Kannisto wrote:
I'm using the new Ultron on my Sony A7C quite happily (not APS-C but 24mp) and I think it works pretty well in my actual use. I stop down to f5.6 for "infinity" shots when looking for corner-to-corner sharpness and I'm very happy with the results there. I typically stop my native lenses down to f5.6 or so for similar "infinity" shots as well and there's no special trickery needed with this lens on 24mp in my view. I typically focus somewhere in the midframe rather than dead center though.
Thanks for the reply and the link to your images Juha. Indeed, they look quite lovely and I certainly don't notice any issues that I would find problematic. Nor do the f2 shots stand out from the rest.
I realised while looking at your photo's that the 1.5x crop from 60mp comes in at 26mp so I can simply crop sample images from the A7riv and be very close to the image circle used and pixel density on 24mp aps-c.
Photo cross posted in the Sony FE Image Thread and taken late yesterday afternoon at 5:17 PM.
Looking at a Red Barn in late afternoon light.
Tripod mounted A7rII Kolari Vision UT sensor modified camera and Voigtlander 28mm f2 Ultron II Asph VM lens; silent shutter.
ISO 100, f8?, 1/160 second.
Exposure Corrected -0.10 Stops.
September 4, 2021
Along the intersection of Muse Road and Loch Valley Road, Weisenberg Township, PA.
I am interested in this lens for use with a Sony a7r4 at f8-11.
I currently use a Minolta M-Rokkor 2.8/28mm which I really enjoy. I am happy with its performance on a Sony. It is good enough for me...
I am thinking that this Voigtlander 28mm is more modern with more elements so is more corrected and better with flare? I shoot alot of backlit scenes. I feel the Rokkor has a 'look' to it - someone said 'moody' - I like this but sometimes want a different look.
So how is this 28mm on a Sony? I will only be using this stopped down...
