Alnitak Posted December 8, 2009 Author Share #41 Posted December 8, 2009 Advertisement (gone after registration) I was afraid of that Sandy. Interestingly enough, I got a replacement copy of my CV 21/4 yesterday, and it looks a lot better. The first one was decentered such that the left edge of the frame was blurred, even at f/8. It had pretty a bad red edge as well. The new one seems to be dead on, nice and sharp, and the red edge is very minor, and using the 21/2.8 11134 profile in the M9 almost perfectly corrects it. Link to post Share on other sites More sharing options...
Advertisement Posted December 8, 2009 Posted December 8, 2009 Hi Alnitak, Take a look here The M9, lenses and the "red edge" problem. I'm sure you'll find what you were looking for!
pes084k1 Posted December 25, 2009 Share #42 Posted December 25, 2009 Dear all, from example posted, it is possible that the optical system over the Leica M9 sensor is shifted with respect to underlying sensors. So the micro-lenses may have a non-symmetric angle of view with respect to incoming rays from left or right. This might result from a sensor design character (e.g., for the space requirement for placement of some conductors within the array), from a non-systematic mask alignment error during sensor building, dependent from a single batch, or from an inexact relative decentering of the lens and the sensor. In any case, some of the causes might be fixed by Kodak, Leica and lens builders, but the cost might be significant and not justified with respect to a software remedium. The CV 12 and 15 mm are high-quality lenses, not fully replaceable by Leica or Zeiss alternatives, especially from flare, distortion and filtering points of view, VERY important for super-wides. Especially the 15 mm Heliar, well managed, is extraordinary for resolution, contrast, purity, etc..I have one sample of it on a Zeiss Ikon SW for special purposes and it does not have any sign of decentering or misfocus and was able to hit the aliasing region on my scanner KM 5400 II at 103 lp/mm (almost twice the M9 capability), full aperture and about 15 mm off center ! The CVs are really retrofocus designs, but retaining a high grade of simmetry, just as the Biogons. I believe that searching within the M9 lens menu or using Cornerfix is the most prudent and classical way to get good results. If the non-sistematic sensor (not lenses!) placement is the M9 problem, the Leica utility should be field and user programmable, and this is risky for the reputation in the presence of Internet forums and unexperienced users. Bye bye Elio Link to post Share on other sites More sharing options...
giordano Posted December 25, 2009 Share #43 Posted December 25, 2009 It's not very hard to test whether the sensor is off-centre. One way is to mount a Visoflex and a lens with a tripod collar that allows at least 180 degrees rotation. Use a good spirit level to set it up on the tripod so the lens axis is exactly horizontal. Measure the height of the lens axis from the floor, and draw a fine horizontal line on the wall a few metres away at the same height. Then rotate the camera 90 degrees left (i.e. portrait orientation), focus on the horizontal line and take a picture. Without disturbing anything else, rotate 180 degrees right and make another exposure. Open the two images on the computer with a program that can report the cursor position. If the two lines are equal distances from the centre of the image, the sensor is centred on the lens axis. If they are different, the sensor is off-centre and you can calculate how much. Not having an M9 I can't try it myself. Would anyone else care to? Link to post Share on other sites More sharing options...
MacSpikes Posted December 25, 2009 Share #44 Posted December 25, 2009 Today I opened a DNG file in Capture One v5 made with the M9 of a snow landscape with the 35mm summicron asph. I wanted to emphasize the green and brown of some trees in the landscape so I increased saturation slightly. Suddenly a red cast was visible on one side of the image. This was clearly apparent since the picture consisted mainly of white snow. I would expect Leica to be able to correct for this lens, but that is not the case under these circumstances. The 35mm is such a common lens that this struck me by surprise. I only increased saturation by 2 points so I did not push things beyond limits. Link to post Share on other sites More sharing options...
Guest mc_k Posted December 26, 2009 Share #45 Posted December 26, 2009 ...If the two lines are equal distances from the centre of the image, the sensor is centred on the lens axis. If they are different, the sensor is off-centre and you can calculate how much... This is like when you flip a transit / theodolite 180 degrees, correct? You take the average to cancel the error from the lens being a little decentered, etc. Have you tried this with another kind of camera, and does it work out ?? Link to post Share on other sites More sharing options...
giordano Posted December 27, 2009 Share #46 Posted December 27, 2009 This is like when you flip a transit / theodolite 180 degrees, correct? You take the average to cancel the error from the lens being a little decentered, etc. Have you tried this with another kind of camera, and does it work out ?? Alas, my surveying never needed more than Abney level and prismatic compass. I don't think it's quite the same, because IIRC you flip the transit 180 degrees about its horizontal axis and then rotate 180 about its vertical axis. I've not done this myself because the question has never arisen. The only lens I have with a rotating tripod mount is a 300mm Nikkor, but if someone cares to drop round with an M9 body we can give it a try (I have an F to M adapter in a shoebox somewhere). Link to post Share on other sites More sharing options...
poe-bear Posted February 12, 2010 Share #47 Posted February 12, 2010 Advertisement (gone after registration) I have a leica m9 + summicron 35 mm. I Have also a soft red edge in my pictures. Have tried cornerfix. It works fine, but i will NOT use it anymore. I've come to the conclusion that cornerfix changes ALL colors in the pictures. Not only the red edge. I've not paid 7500 euro to have the perfect picture, and then overlay it with a cyan colorcast. my advice: use the graduated filter tool in lightroom. I've did 4 filters on one picture. 3 on the left side/ 1 on the top of the image. (180-200 degrees / 2 to 4 percent) One you have done that, save it with a preset. It works! Link to post Share on other sites More sharing options...
john bartlett Posted February 24, 2010 Share #48 Posted February 24, 2010 Hello Jeff Quote "I'm hoping to further test this concept of decentering as the primary cause by trying a couple of different copies of the CV 15mm in the coming weeks. Ideally I would be able to try it with more than one M9, but that might be a bit difficult to achieve." Have you had the opportunity to do any of this? John R B Link to post Share on other sites More sharing options...
Alnitak Posted February 24, 2010 Author Share #49 Posted February 24, 2010 Hello Jeff Quote "I'm hoping to further test this concept of decentering as the primary cause by trying a couple of different copies of the CV 15mm in the coming weeks. Ideally I would be able to try it with more than one M9, but that might be a bit difficult to achieve." Have you had the opportunity to do any of this? John R B Unfortunately, no, it did not work out. The evidence is mounting that this is a complicated problem, and lens decentering likely plays some role, but it's not the only factor or even the primary factor. Jeff Link to post Share on other sites More sharing options...
hoppyman Posted February 25, 2010 Share #50 Posted February 25, 2010 If lens decentring proved to be a factor, it may not be applicable to every lens of course. Based on Erwin Putts' test reports, this may be more significant for CV lenses. Those are out of Leica's control/sphere of interest naturally. Link to post Share on other sites More sharing options...
Alnitak Posted February 25, 2010 Author Share #51 Posted February 25, 2010 If lens decentring proved to be a factor, it may not be applicable to every lens of course. Based on Erwin Putts' test reports, this may be more significant for CV lenses. Those are out of Leica's control/sphere of interest naturally. I think that's the whole idea, especially as to why some copies of certain lens models seem to have a problem when many others (if not most) of the same model do not. Voigtlander definitely has a consistency issue with centering, something I have experienced first hand, and it also does clearly effect the red edge issue. Jeff Link to post Share on other sites More sharing options...
smb Posted March 6, 2010 Share #52 Posted March 6, 2010 I am trying to follow this thread and the "red edge" problem. From what I have read the "red edge" appears only on wide angle CV lenses. Is this correct? Does it appear on 28mm lenses Leica or Zeiss or any of the Zeiss lenses? From 35mm and longer there does not seem to be any reported problems on all three makes...Leica, Zeiss, CV---Is this correct? Is it possible that we could develope a list of lenses that have the "red edge" problem? Link to post Share on other sites More sharing options...
k-hawinkler Posted March 7, 2010 Share #53 Posted March 7, 2010 I am trying to follow this thread and the "red edge" problem. From what I have read the "red edge" appears only on wide angle CV lenses. Is this correct? Does it appear on 28mm lenses Leica or Zeiss or any of the Zeiss lenses? From 35mm and longer there does not seem to be any reported problems on all three makes...Leica, Zeiss, CV---Is this correct? Is it possible that we could develope a list of lenses that have the "red edge" problem? I believe that was attempted here: http://www.l-camera-forum.com/leica-forum/leica-m9-forum/114311-red-edge-lenses.html Link to post Share on other sites More sharing options...
lars_bergquist Posted March 7, 2010 Share #54 Posted March 7, 2010 I can attest that Cosina do often produce lenses with very noticeable decentering problems. Much of the price you pay for a Leica or Zeiss lens is actually the price of careful, step-by step control of tolerances during assembly. Leica are fanatical about this and do not let through errors of more than 2 micron. Check, adjust the mount, reassemble, check again ... all this done manually by very skilled workers paid in euros. This for instance is a very large part of the explanation why the new Noctilux was not available off the shelf until a year after the introduction. It took time to run in this very exacting process -- and it is of course a very exacting lens, close to the limit of the doable. You may not appreciate this until you find that a lens you have bought is noticeably soft on one side. So I buy Leica or Zeiss, manufacturers who know that the goodwill of the brand name is a very large part of their capital. But the left-red-edge problem (and the concomitant green-right-edge one) are not per se results of decentering, though decentering can probably accentuate them. The old man from the Age of Red Eyes Link to post Share on other sites More sharing options...
chris_tribble Posted March 7, 2010 Share #55 Posted March 7, 2010 Gentlemen (haven't noticed any ladies on this discussion...) - is this a case of things being invisible until you see them? I've gone back over all the white snow images I've taken with the M9 and can't for the life of me see any red-edge with 35 cron mk IV or 28 cron asph. A couple of examples below. Can any one show me the red edge? I can see it on my 18 Zeiss and it's a slight issue with the 21 Elmarit (non-asph). But not the 28 or 35. I'm not trying to fight a rear-guard "defend the M9" campaign, but I do get a slight sense that the forum is getting a bit obsessed with the problems that a very small (though real) number of people have faced, and no longer represents the thousands of (apparently) extremely satisfied M9 users who are just getting on with taking photographs... 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! 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/105486-the-m9-lenses-and-the-red-edge-problem/?do=findComment&comment=1250140'>More sharing options...
Alnitak Posted March 7, 2010 Author Share #56 Posted March 7, 2010 Chris, I agree with you. I just can't find any issue with any of my Leica lenses except my 21/2.8 Elmarit ASPH, which has a very slight problem. I'm going out shooting around London today, and will just enjoy my lenses and M9. Jeff Link to post Share on other sites More sharing options...
euston Posted March 7, 2010 Share #57 Posted March 7, 2010 - is this a case of things being invisible until you see them? It may be but here's one of mine that is a similar shot to yours, though not as accurately exposed as yours, which may contribute to the problem. This was taken with an Elmarit 28/2.8 asph and processed through ACR on the default settings. The discoloration is very easy to correct but I do rather feel that one shouldn't have to. I took quite a few snow shots and this is by far the worst for red contamination but it did appear on all of them. There is also cyan discoloration on the other side. It's a new lens. Do you think it should go back under warranty? 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! 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/105486-the-m9-lenses-and-the-red-edge-problem/?do=findComment&comment=1250232'>More sharing options...
chris_tribble Posted March 7, 2010 Share #58 Posted March 7, 2010 Looking at Jon Slack's post (http://www.l-camera-forum.com/leica-forum/leica-m9-forum/114311-red-edge-lenses.html#post1211158) it looks like the Elmarit asph is one of the lenses that needs work on in firmware. My understanding from a recent exchange is that the NEW lenses are the ones that are being given immediate attention - so I'd hold on to yours until the new firmware is released (week or two I hear...) Best C: Link to post Share on other sites More sharing options...
euston Posted March 7, 2010 Share #59 Posted March 7, 2010 Looking at Jon Slack's post (http://www.l-camera-forum.com/leica-forum/leica-m9-forum/114311-red-edge-lenses.html#post1211158) it looks like the Elmarit asph is one of the lenses that needs work on in firmware. My understanding from a recent exchange is that the NEW lenses are the ones that are being given immediate attention - so I'd hold on to yours until the new firmware is released (week or two I hear...) Best C: Thanks! That sounds like good advice. Link to post Share on other sites More sharing options...
lars_bergquist Posted March 7, 2010 Share #60 Posted March 7, 2010 My own suspicion is that this may well be a matter, not only of the lens on the camera, but of the little lenses in front of the sensor. At the very least, it cannot simply be that the camera lens, or some camera lenses, project red-biased light in on direction and green-biased in another. The phenomenon is at least roughly correlated with the focal length, and does not vary all over the place, so it does clearly have to do with the angle of incidence on the sensor. Hence, it is not a matter of faulty individual camera lenses. I would at least expect an explanation from Leica. Published by way of an article in the next issue of LFI, perhaps. They cannot very well avoid thinking about the phenomenon. The old man from the balmy Age of Black and White Link to post Share on other sites More sharing options...
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