lct Posted May 17, 2021 Share #61 Posted May 17, 2021 Advertisement (gone after registration) Question: Green and Purple or Blue and Purple? Answer: Green, Purple and Blue . BTW comes from an apo lens so your loca/laca thingies look pretty ridiculous . Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 1 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/320955-90mm-apo-summicron-m-not-apochromatic/?do=findComment&comment=4202547'>More sharing options...
Advertisement Posted May 17, 2021 Posted May 17, 2021 Hi lct, Take a look here 90mm Apo-Summicron-M not apochromatic?. I'm sure you'll find what you were looking for!
pedaes Posted May 17, 2021 Share #62 Posted May 17, 2021 @LarsHP You might find this useful in relation to definition of APO - see post #14 1 Quote Link to post Share on other sites More sharing options...
leicameech Posted May 17, 2021 Share #63 Posted May 17, 2021 Wouldn't it be expected that a Leica lens would perform its best on a Leica camera, and even more so on the camera the lens was designed to be used on? Why would Leica have Sony, Nikon, Canon bodies to test their lenses on. The only reason to do so would be to ensure good performance if Leica was making lenses in those mounts. I would expect there to be Sigma FPs and Panasonic S1 series cameras in the R&D department or optics department or whatever it is long before I'd expect Leica to be running MTF tests on lenses when mounted to anything else besides Leica. The manufacturers themselves (Nikon, Sony etc.) don't even make the adapter to adapt the Leica M lens to their system. Leica doesn't either. So on the one hand you're nerding out about the subtleties of LoCa and LaCa and micro lenses and all of this scientific stuff, but on the other you're doing a pretty un-scientific test -- using a rangefinder lens with a 3rd party adapter to a camera that Leica likely hasn't ever tested it on, and obviously didn't test it on when they made the lens ~15-20 years ago. Even if they did test it, why should they care about the result? I wouldn't. You've compared two "true APO" lenses to your results, but the two lenses you've compared were tested on cameras with the same lens mount as the lenses themselves. They're also totally different lenses from the lens you're comparing them to in every way except maximum aperture and that they have APO in their name. For a true comparison to those lenses, you'd at least have to put the 90 APO on an M camera. I suspect you still wouldn't like the results, but it is hard to ignore that you're stacking the deck against the Leica in every way imaginable as a starting point here. Fwiw, Leica doesn't prioritize APO performance wide-open only, or at a particular f/stop only. They correct at every aperture, every focal distance. With this approach, the end result is likely going to end up being some flavor of a compromise. Still, I'd say they do a pretty good job The M lens' size is often taken for granted, and even the Voigtlander APO lenses are both significantly larger than their Leica counterparts. Is there a better-performing short telephoto than the 90 APO given its size, in your opinion? By the way -- the 75 isn't as good as the 90 APO (on paper, anyway), but if you get your hands on one of those, I look forward to hearing your thoughts! 3 1 Quote Link to post Share on other sites More sharing options...
lct Posted May 17, 2021 Share #64 Posted May 17, 2021 On 3/4/2021 at 6:23 PM, jonoslack said: I must confess I'm not certain whether this lens is Apochromatic in the true technical sense or not Good to know. I have zero technical clue about M 35/2 or M 90/2 lenses but avoiding purple fringing on the latters proves rather easy: 1. Choose the better lens CA wise, namely Summicron 90/2 v2 (11123). Big but superb otherwise. 2. Avoid the weaker one CA wise, namely Summicron 90/2 v3 (11136). More compact, gorgeous on portraits but CA is not its forte. 3. Choose the better compromise, namely Summicron 90/2 apo (11884). Another superb lens the same size as v3. Just avoid overexposures which is sometimes difficult (branches, sea, snow) and you'll get results like this (90/2 apo, f/2, EV -1, A7r2 mod, AF adapt., full frame and 100% crop). Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 3 2 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/320955-90mm-apo-summicron-m-not-apochromatic/?do=findComment&comment=4202620'>More sharing options...
capo di tutti capi Posted May 17, 2021 Share #65 Posted May 17, 2021 (edited) 30 minutes ago, leicameech said: Wouldn't it be expected that a Leica lens would perform its best on a Leica camera, and even more so on the camera the lens was designed to be used on? Some cameras from other manufacturers are very good at cleaning the CA of old lenses. Even better than with native lenses. What you are showing here, I have not seen in a bunch of leica lens + camera not leica. When used a few years ago. A lot depends on the camera. Edited May 17, 2021 by capo di tutti capi Quote Link to post Share on other sites More sharing options...
ianman Posted May 17, 2021 Share #66 Posted May 17, 2021 yes but if I zoom to 28.000.003%, I can see some green in your leaves!!!! 😱 Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! oh, and some purple.... strange that 🤨 4 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! oh, and some purple.... strange that 🤨 ' data-webShareUrl='https://www.l-camera-forum.com/topic/320955-90mm-apo-summicron-m-not-apochromatic/?do=findComment&comment=4202624'>More sharing options...
adan Posted May 17, 2021 Share #67 Posted May 17, 2021 Advertisement (gone after registration) 1) chromatic abberations produce all kinds of color fringes. The only commonality is that the fringes are complementary colors of the spectrum: red-cyan, green-purple, yellow-blue and so on. If the red light wanders away from the correct path (latin: ab = "away," erro - "wander") that results in part of the image lacking in red that should be there (appearing cyan), and parts of the image having excess red that shouldn't be there (appearing red). If one doesn't know that chromatic aberrations can easily produce yellow, orange, green, or red fringes, that just shows that one's knowledge of aberrations is incomplete and faulty. I've used the 75 Summilux and 135 Tele-Elmar, and both produce red/cyan LoCA, with the red fringe being quite visible. (neither, of course, is claimed to be APO). Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 2) Generally, lenses are categorized by how many specific wavelengths they focus in the same plane. Plain lenses focus one wavelength correctly Achromatic lenses (since 1730 or thereabouts) focus two wavelengths in the same plane Apochromatic lenses focus three wavelengths in the same plane Superachromatic lenses focus four wavelengths n the same plane It should be noted that often one of the corrected wavelengths is not in the visible part of the EM spectrum - it may a UV or IR wavelength. That does not change whether the lens qualifies as achro, APO or SuperAPO. it should be noted that there are about 370 wavelengths in the visible color spectrum (using nanometers to define wavelengths - obviously in a spectrum there can be an infinite number of wavelengths - e.g. λ=523.51427 nanometers). So even a Superachromat will not focus most colors in exactly the correct plane. But the weaving back and forth to cross the plane of focus at four points generally means other colors will be better (but not perfectly) corrected. https://upload.wikimedia.org/wikipedia/commons/2/23/Comparison_chromatic_focus_shift_plots.svg 3) as has been repeated as nauseam, a lens qualifies as apochromatic if it focuses 3 wavelengths in the same plane. What it does away from the plane of focus is irrelevant. If one chooses to hold the opinion that what happens outside the plane of focus (e.g. in blurry backgrounds) should be included, one has the right to hold such an opinion. Just as one has the right to hold the opinion that the earth is flat. However, if one chooses to express such an opinion to a professional trained optical or geo scientist, one should allow extra time. So that the scientist can quit laughing, and get up off the floor and back into her chair. My cats have opinions - they are not an especially valuable commodity. 2 7 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 2) Generally, lenses are categorized by how many specific wavelengths they focus in the same plane. Plain lenses focus one wavelength correctly Achromatic lenses (since 1730 or thereabouts) focus two wavelengths in the same plane Apochromatic lenses focus three wavelengths in the same plane Superachromatic lenses focus four wavelengths n the same plane It should be noted that often one of the corrected wavelengths is not in the visible part of the EM spectrum - it may a UV or IR wavelength. That does not change whether the lens qualifies as achro, APO or SuperAPO. it should be noted that there are about 370 wavelengths in the visible color spectrum (using nanometers to define wavelengths - obviously in a spectrum there can be an infinite number of wavelengths - e.g. λ=523.51427 nanometers). So even a Superachromat will not focus most colors in exactly the correct plane. But the weaving back and forth to cross the plane of focus at four points generally means other colors will be better (but not perfectly) corrected. https://upload.wikimedia.org/wikipedia/commons/2/23/Comparison_chromatic_focus_shift_plots.svg 3) as has been repeated as nauseam, a lens qualifies as apochromatic if it focuses 3 wavelengths in the same plane. What it does away from the plane of focus is irrelevant. If one chooses to hold the opinion that what happens outside the plane of focus (e.g. in blurry backgrounds) should be included, one has the right to hold such an opinion. Just as one has the right to hold the opinion that the earth is flat. However, if one chooses to express such an opinion to a professional trained optical or geo scientist, one should allow extra time. So that the scientist can quit laughing, and get up off the floor and back into her chair. My cats have opinions - they are not an especially valuable commodity. ' data-webShareUrl='https://www.l-camera-forum.com/topic/320955-90mm-apo-summicron-m-not-apochromatic/?do=findComment&comment=4202626'>More sharing options...
LarsHP Posted May 17, 2021 Author Share #68 Posted May 17, 2021 (edited) 4 hours ago, Robert Blanko said: IMHO, this cannot be the result of only LoCas, as they usually have a color depending on whether the object is in front or behind the focus plane (cf. also the link in ianman‘s post) - whereas here the objects seem to be located in the same plane but there are nevertheless two colors. https://diglloyd.com/prem/s/MSI/publish/Optical-LOCA-secondary.htmlhttps://diglloyd.com/prem/s/MSI/publish/Optical-LOCA-secondary.html Thanks for the link. As you can see in the image in the link if you check it properly, there is green and purple both in front of and behind the plane of focus. It's just a matter of degree: mostly green behind and mostly purple in front of the point of focus. Edited May 17, 2021 by LarsHP Quote Link to post Share on other sites More sharing options...
LarsHP Posted May 17, 2021 Author Share #69 Posted May 17, 2021 1 hour ago, pedaes said: @LarsHP You might find this useful in relation to definition of APO - see post #14 Thanks for the tip! Interesting read. Don't know exactly what to make of it in relation to my issue with the M 90 Apo. If what he says is correct, it means that the "apo" designation doesn't mean that the lens is apochromatic since that would introduce unwanted optical behavior. To me - and to most people in photography I think - "apo" is short for apochromatic, and this points to extraordinarily reduced chromatic aberrations. Quote Link to post Share on other sites More sharing options...
leicameech Posted May 17, 2021 Share #70 Posted May 17, 2021 25 minutes ago, capo di tutti capi said: Some cameras from other manufacturers are very good at cleaning the CA of old lenses. Even better than with native lenses. What you are showing here, I have not seen in a bunch of leica lens + camera not leica. When used a few years ago. A lot depends on the camera. While I don't doubt this, and also haven't seen direct results one way or the other, it would not be possible to know that this would be the case here, since OP has never tried the lens on the native camera. Though what you point out can happen, it's equally likely (probably more likely) that the opposite is true, especially when applied to what we're discussing here. If the lens performs anything other than equally as good or better on an M than on OP's Sony with the modified sensor by someone who is also not Leica, then the title of this thread may as well be "the 90 APO sucks and is a waste of money." The 90 APO has been around a long time, but it is still a current lens, and therefore a Leica camera that comes out is surely subjected to testing with this lens along with all others in current-production. I don't think OP will be happy with any M APO lens, though. Quote Link to post Share on other sites More sharing options...
LarsHP Posted May 17, 2021 Author Share #71 Posted May 17, 2021 2 minutes ago, leicameech said: (...) since OP has never tried the lens on the native camera. Though what you point out can happen, it's equally likely (probably more likely) that the opposite is true, especially when applied to what we're discussing here. If the lens performs anything other than equally as good or better on an M than on OP's Sony with the modified sensor by someone who is also not Leica, then the title of this thread may as well be "the 90 APO sucks and is a waste of money." The 90 APO has been around a long time, but it is still a current lens, and therefore a Leica camera that comes out is surely subjected to testing with this lens along with all others in current-production. I don't think OP will be happy with any M APO lens, though. I have to correct a few things here. You assume several things here and at least three are wrong. 1) It is not true that I haven't tried the M 90 Apo on a Leica camera. I did actually try such a lens on an M 240. To be precise and honest, it was not my current sample of the lens though, but an M 90 Apo it was. That lens also showed chromatic aberrations like I see now, but the test shots weren't as challenging as the ones I have posted here. Still, it was enough for me to skip buying the lens at that time. 2) I don't use a modified Sony camera for these shots. It's a sensor modified Nikon Z6. (The sensor glass has been removed for ultra-thin glass which makes the sensor stack about the same thickness as a digital Leica M camera.) As I have mentioned a few times now, in post #29 I have linked to an infinity shot with the lens wide open on my Z6UT, and in that image it performs flawlessly. If there were any problems with the sensor-camera relation, then it would show it in such a scene the most. 3) In the very first post, plus in posts after that, I also stated the impressive qualities of the M 90 Apo. This makes it inappropriate to claim that I just as well could have called the thread "the 90 APO sucks and is a waste of money". Quote Link to post Share on other sites More sharing options...
leicameech Posted May 17, 2021 Share #72 Posted May 17, 2021 9 minutes ago, LarsHP said: I have to correct a few things here. You assume several things here and at least three are wrong. 1) It is not true that I haven't tried the M 90 Apo on a Leica camera. I did actually try such a lens on an M 240. To be precise and honest, it was not my current sample of the lens though, but an M 90 Apo it was. That lens also showed chromatic aberrations like I see now, but the test shots weren't as challenging as the ones I have posted here. Still, it was enough for me to skip buying the lens at that time. 2) I don't use a modified Sony camera for these shots. It's a sensor modified Nikon Z6. (The sensor glass has been removed for ultra-thin glass which makes the sensor stack about the same thickness as a digital Leica M camera.) As I have mentioned a few times now, in post #29 I have linked to an infinity shot with the lens wide open on my Z6UT, and in that image it performs flawlessly. If there were any problems with the sensor-camera relation, then it would show it in such a scene the most. 3) In the very first post, plus in posts after that, I also stated the impressive qualities of the M 90 Apo. This makes it inappropriate to claim that I just as well could have called the thread "the 90 APO sucks and is a waste of money". Don't get me wrong, I mean no disrespect. I mentioned before that this thread was entertaining, and you seem as unhappy with this lens as anyone I've ever heard of, so I cannot help but find the entire premise of this thread quite amusing. My mistake on the Sony vs Nikon, though really the fact that it's a non-Leica with a modified sensor doesn't change the essence of what I was saying in the first place. It's not so much even about the results, which I still believe to be very good anyway, but that you're disappointed in a lens that you're using on another manufacturer's camera with a change that even the manufacturer doesn't seem to think improves the performance of their cameras (otherwise they'd be releasing the camera with the modification to begin with). Regarding #3, you're making my point for me. You said that on an M240 the 90 APO showed similar results. Not worse, not better, more-or-less. This was the bare minimum of performance I said I would have expected, and that the Leica lens on Leica body shouldn't perform any worse than on your franken-Nikon. So that brings us back to where we began. It's called an APO lens, you don't like the results, but the other things going for it that make it exceptional and prevent you from using the other two you threw in for comparison as substitutes for it (size, weight, ergonomics etc.). Essentially you're saying that the lens should be called, at best, "as APO as we can get it for an M lens." That's fair enough, but gauging by replies in this thread from others, I'm not alone in that I think your expectations are even higher than Leica's. Zero chromatic aberration in a tiny lens is not a walk in the park. If it were, every manufacturer would do it. I cannot help but feel that you're singling out the optical performance in the harshest testing (for any lens) and taking the rest of what this lens has going for it for granted. You have to admit it at least a little bit.. I mean we're talking about 100% crops of bokeh mountains! 1 Quote Link to post Share on other sites More sharing options...
happymac Posted May 17, 2021 Share #73 Posted May 17, 2021 Discussions like this let me think about leaving this forum and using the gained time for taking photographs with my APO 90, which I‘ve owned for more than 20 years. 5 2 Quote Link to post Share on other sites More sharing options...
M11 for me Posted May 17, 2021 Share #74 Posted May 17, 2021 Can you not do both? Quote Link to post Share on other sites More sharing options...
capo di tutti capi Posted May 17, 2021 Share #75 Posted May 17, 2021 (edited) 1 hour ago, leicameech said: While I don't doubt this, and also haven't seen direct results one way or the other, it would not be possible to know that this would be the case here, since OP has never tried the lens on the native camera. Though what you point out can happen, it's equally likely (probably more likely) that the opposite is true, especially when applied to what we're discussing here. If the lens performs anything other than equally as good or better on an M than on OP's Sony with the modified sensor by someone who is also not Leica, then the title of this thread may as well be "the 90 APO sucks and is a waste of money." The 90 APO has been around a long time, but it is still a current lens, and therefore a Leica camera that comes out is surely subjected to testing with this lens along with all others in current-production. I don't think OP will be happy with any M APO lens, though. The Leica has many kinds of sensors. Each time they improved. Added microlenses, changed the distance between pixels. It is probably impossible to account for all lens combinations and all cameras. Edited May 17, 2021 by capo di tutti capi 1 Quote Link to post Share on other sites More sharing options...
LarsHP Posted May 17, 2021 Author Share #76 Posted May 17, 2021 (edited) Just a real quick and dirty shot (it's not even straight!) showing the 90mm Apo-Summicron-M wide open at infinity. This clearly shows that the lens performs GREAT on the Nikon Z6UT. It's sharp corner to corner and except for a little manual vignetting correction, there is no lens corrections applied (including the "Remove chromatic aberration" ticked off). In other words, there is no reason to assume that it's the sensor-lens relationship that provoke LoCA. LaCA might have been an issue if the sensor glass was too thick as well as "smearing". However, there is none. To sum up my take on what this thread is saying, I seem to have higher expectations regarding how well the 90mm Apo-Summicron-M is corrected for longitudinal chromatic aberrations than what others perhaps have. These expectations were based on other lenses with "apo" designation that I have tested - as well as the price tag, to be honest. When I buy a $5000 lens, I expect it to be clearly better than a lens at around $1000 or so (this includes my Elmarit-M). The one excuse I can see is that M lenses are more compact and that the lens is a relatively old design (being introduced in 1998). It's also worth noting that there still isn't any better 90mm offering in M mount. Hopefully that will change soon. 🙄 (If Cosina Voigtländer should read this: Please make a 90mm f/2 Apo-Lanthar in M mount soon.) 😁 Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Edited May 17, 2021 by LarsHP 2 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/320955-90mm-apo-summicron-m-not-apochromatic/?do=findComment&comment=4202716'>More sharing options...
ianman Posted May 17, 2021 Share #77 Posted May 17, 2021 5 minutes ago, LarsHP said: It's also worth noting that there still isn't any better 90mm offering in M mount. Hopefully that will change soon. I certainly hope so. Mine is going in the trash first thing in the morning! 4 Quote Link to post Share on other sites More sharing options...
lct Posted May 17, 2021 Share #78 Posted May 17, 2021 (edited) 18 minutes ago, LarsHP said: When I buy a $5000 lens, I expect it to be clearly better than a lens at around $1000 or so. The one excuse I can see is that M lenses are more compact and that the lens is a relatively old design (being introduced in 1998). It's also worth noting that there still isn't any better 90mm offering in M mount. Hopefully that will change soon. What excuse? Why would this superb lens change in any way? Sorry but i seem to recall that when you came on this forum it was to complain against Leica prices in the first place and claiming that other lenses are at least as good for a fraction of the price. Please reassure me you're not trying to support that sort of claim by disturbing good faith colleagues trying to help you are you. Edited May 17, 2021 by lct 5 Quote Link to post Share on other sites More sharing options...
jaapv Posted May 17, 2021 Share #79 Posted May 17, 2021 17 minutes ago, LarsHP said: Just a real quick and dirty shot (it's not even straight!) showing the 90mm Apo-Summicron-M wide open at infinity. This clearly shows that the lens performs GREAT on the Nikon Z6UT. It's sharp corner to corner and except for a little manual vignetting correction, there is no lens corrections applied (including the "Remove chromatic aberration" ticked off). In other words, there is no reason to assume that it's the sensor-lens relationship that provoke LoCA. LaCA might have been an issue if the sensor glass was too thick as well as "smearing". However, there is none. To sum up my take on what this thread is saying, I seem to have higher expectations regarding how well the 90mm Apo-Summicron-M is corrected for longitudinal chromatic aberrations than what others perhaps have. These expectations were based on other lenses with "apo" designation that I have tested - as well as the price tag, to be honest. When I buy a $5000 lens, I expect it to be clearly better than a lens at around $1000 or so (this includes my Elmarit-M). The one excuse I can see is that M lenses are more compact and that the lens is a relatively old design (being introduced in 1998). It's also worth noting that there still isn't any better 90mm offering in M mount. Hopefully that will change soon. 🙄 (If Cosina Voigtländer should read this: Please make a 90mm f/2 Apo-Lanthar in M mount soon.) 😁 Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! And therein lies the rub: APO is not a quality indication, although marketing would like to make it so. Like the PRO indications on anything from skis to toasters. 6 Quote Link to post Share on other sites More sharing options...
pippy Posted May 17, 2021 Share #80 Posted May 17, 2021 48 minutes ago, LarsHP said: ...It's also worth noting that there still isn't any better 90mm offering in M mount.... Is it too much to hope that you might try out a Thambar sometime soon and share your views on its performance with us? Philip. 6 Quote Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.