sandymc Posted October 27, 2009 Share #61 Posted October 27, 2009 Advertisement (gone after registration) How vignetting of a lens is visible on the photo is very much depending of exposure. Vignetting makes the edges darker. If one edge is overexposed vignetting makes it look just right When I noticed the issue of red shift first with the 18mm Super-Elmar with the M8 I was sure that it was only on the left side. The M8 does occasionally either overcorrect or under-correct slightly. However, all jokes about elves aside, the M9 is different in two key respects: (1) On the M8, it really is "slightly" - other than really exotic lighting conditions, you have to be looking at a grey card image or a vignetting plot to see it; on the M9, the problem is instantly visible in normal images shot in daylight. Bear in mind, previous versions of CornerFix couldn't correct for this, and I've never had a CornerFix user notice this as an issue on the M8. (2) there is a "bias to left" on the M9 that I haven't seen on the M8. That bias isn't just a visual thing - the vignetting plots I posted show that its real: ChromaSoft: Vignetting Correction Issues on the Leica M9 Personally, I think it likely that this can be solved satisfactorily in firmware - however given that the problem is clearly quite widespread (there aren't that many M9's out there yet, and there are a lot of people that have seen this problem), I think Leica would be well advised to clarify what is going on. I know several people have sent queries to Leica on this - hopefully they will respond Sandy Link to post Share on other sites More sharing options...
Advertisement Posted October 27, 2009 Posted October 27, 2009 Hi sandymc, Take a look here What would happen if the M9 was a flawed camera?. I'm sure you'll find what you were looking for!
thrice Posted October 27, 2009 Share #62 Posted October 27, 2009 Sandy, I would be rather worried about this problem if it weren't for cornerfix As it stands I'm not too concerned, I'm sure Leica will make appropriate firmware corrections and in the interim cornerfix will repair any affected images. Thankyou! Link to post Share on other sites More sharing options...
luigi bertolotti Posted October 27, 2009 Share #63 Posted October 27, 2009 The M8 does occasionally either overcorrect or under-correct slightly. However, all jokes about elves aside, the M9 is different in two key respects: (1) On the M8, it really is "slightly" - other than really exotic lighting conditions, you have to be looking at a grey card image or a vignetting plot to see it; on the M9, the problem is instantly visible in normal images shot in daylight. Bear in mind, previous versions of CornerFix couldn't correct for this, and I've never had a CornerFix user notice this as an issue on the M8. (2) there is a "bias to left" on the M9 that I haven't seen on the M8. That bias isn't just a visual thing - the vignetting plots I posted show that its real: ChromaSoft: Vignetting Correction Issues on the Leica M9 Personally, I think it likely that this can be solved satisfactorily in firmware - however given that the problem is clearly quite widespread (there aren't that many M9's out there yet, and there are a lot of people that have seen this problem), I think Leica would be well advised to clarify what is going on. I know several people have sent queries to Leica on this - hopefully they will respond Sandy Great link, Sandy, compliments for yours and others' work - very clear - : the "bias to left" is really an odd phenomenon... but I haven't understood well if it is typical of the SE18 or has emerged as clearly also with other lenses... a previous post from Muarizio - Summicron 28 - suggests it is so... but I would like to see more examples with the "white wall - lab environment" you used in the above link. Link to post Share on other sites More sharing options...
Ario Arioldi Posted October 27, 2009 Share #64 Posted October 27, 2009 This is an example with CV 15 uncoded (Milano's blue ski 2 stop overxeposed). The bias seeems not only to the left but also to the bottom. With this lens I'm not able to get a neutral correction with CornerFix, some residual magenta is always present. Cheers, Ario 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/101538-what-would-happen-if-the-m9-was-a-flawed-camera/?do=findComment&comment=1091479'>More sharing options...
marknorton Posted October 27, 2009 Share #65 Posted October 27, 2009 Sandy, I would be rather worried about this problem if it weren't for cornerfix As it stands I'm not too concerned, I'm sure Leica will make appropriate firmware corrections and in the interim cornerfix will repair any affected images. Thankyou! It's great we have CornerFix, even greater that it's available free of charge but I hardly think Leica should be washing their hands of the problem just because CornerFix exists. More than any images, the graphs on Sandy's link suggest there's something odd going on and we really do need Leica to tell us what it is. I just hope they're not hiding under their desks in Solms with their fingers in their ears... Link to post Share on other sites More sharing options...
sandymc Posted October 27, 2009 Share #66 Posted October 27, 2009 The bias seeems not only to the left but also to the bottom. Yes, that's right. Actually, on e.g., Tim's 18mm f/3.8 the measured bias from the center in pixels is about +62 horizontally and -138 vertically. AKA the offset is actually greater vertically than horizontally. Why it usually shows more to left is that what you see is usually the horizontal offset, because the horizontal side is a lot "longer" (has more pixels), and the vignetting gets disproportionately worse the further you get out, because of the non-linear curve that the vignetting follows. So you see red to left. Sandy Link to post Share on other sites More sharing options...
pgk Posted October 27, 2009 Share #67 Posted October 27, 2009 Advertisement (gone after registration) This is an example with CV 15 uncoded (Milano's blue ski 2 stop overxeposed). The bias seeems not only to the left but also to the bottom.With this lens I'm not able to get a neutral correction with CornerFix, some residual magenta is always present. Cheers, Ario Hmmmm. Couldn't this also relate to an optical alignment problem? Or a mix of problems? Does it happen with any other lenses on the same body? I assume that cornerfix operates symmetrically so I'm not surprised that it can't deal with this. Link to post Share on other sites More sharing options...
marknorton Posted October 27, 2009 Share #68 Posted October 27, 2009 Actually, on e.g., Tim's 18mm f/3.8 the measured bias from the center in pixels is about +62 horizontally and -138 vertically. At a pixel pitch of 6.8 um, that's 0.42mm horizontally and 0.88mm vertically, so just supposing the sensor is off centre, it would need to be moved half of those distances to even things out. Link to post Share on other sites More sharing options...
Ario Arioldi Posted October 27, 2009 Share #69 Posted October 27, 2009 Hmmmm. Couldn't this also relate to an optical alignment problem? Or a mix of problems? Does it happen with any other lenses on the same body? I assume that cornerfix operates symmetrically so I'm not surprised that it can't deal with this. Yes, it happens also with other lenses, this is for instance a pic, same conditions as the previous one, taken with ZM 18. 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/101538-what-would-happen-if-the-m9-was-a-flawed-camera/?do=findComment&comment=1091526'>More sharing options...
sandymc Posted October 27, 2009 Share #70 Posted October 27, 2009 Hmmmm. Couldn't this also relate to an optical alignment problem? Or a mix of problems? Does it happen with any other lenses on the same body? I assume that cornerfix operates symmetrically so I'm not surprised that it can't deal with this. Yes, it could easily be an optical alignment problem. In fact, that was my first assumption. The issue that's got everybody scratching their heads is why its always to the left; If this were manufacturing variations, we'd expect to see a spread round the center. And it not just Leica lenses, CV ones show this as well. Re CornerFix, up till V1.3.0.0 it was indeed entirely symmetrical. V1.3.0.0 upwards have asymmetrical correction, and de-centering compensation, which is why it can can now correct the problem. Sandy Link to post Share on other sites More sharing options...
Mauribix Posted October 27, 2009 Share #71 Posted October 27, 2009 Sandy, your work is so much appreciated. You're my hero! Link to post Share on other sites More sharing options...
ArtZ Posted October 28, 2009 Author Share #72 Posted October 28, 2009 The M8 does occasionally either overcorrect or under-correct slightly. However, all jokes about elves aside, the M9 is different in two key respects: (1) On the M8, it really is "slightly" - other than really exotic lighting conditions, you have to be looking at a grey card image or a vignetting plot to see it; on the M9, the problem is instantly visible in normal images shot in daylight. Bear in mind, previous versions of CornerFix couldn't correct for this, and I've never had a CornerFix user notice this as an issue on the M8. (2) there is a "bias to left" on the M9 that I haven't seen on the M8. That bias isn't just a visual thing - the vignetting plots I posted show that its real: ChromaSoft: Vignetting Correction Issues on the Leica M9 Personally, I think it likely that this can be solved satisfactorily in firmware - however given that the problem is clearly quite widespread (there aren't that many M9's out there yet, and there are a lot of people that have seen this problem), I think Leica would be well advised to clarify what is going on. I know several people have sent queries to Leica on this - hopefully they will respond Sandy Sandy, You said in another thread correcting vignetting (and magenta cast) with Cornerfix increases noise on corrected areas. Now my question is: If Leica corrects this problem with new firmware, noise will also increase? And if your answer is yes, the noise will increase as you stated before in the other thread? Please also note that the corners of lens such as the CV take a lot of correction, which increases noise in the corners considerably - this is inherent in any correction process, be it by CornerFix or in-camera. For example, on a lens that vignettes by four stops in the corners - not uncommon on the M9 - shooting at ISO 640 and then correcting means ISO 2500 noise levels in the corners. So to whatever extent possible you should try to shoot at low ISO when using wide angle lenses on the M9 Thank you Sandy Link to post Share on other sites More sharing options...
sandymc Posted October 28, 2009 Share #73 Posted October 28, 2009 You said in another thread correcting vignetting (and magenta cast) with Cornerfix increases noise on corrected areas. Now my question is: If Leica corrects this problem with new firmware, noise will also increase? And if your answer is yes, the noise will increase as you stated before in the other thread? Hopefully not, because the "red edge" problem is over-correction, so the firmware modification will be to reduce the amount of correction, so if anything there should be a little less noise. What might however happen, depending on the root cause of the red edges, is that the right hand edge will be become a little under-corrected, so cyan. However that is less visible than overcorrection, so would be a worthwhile trade-off. Sandy Link to post Share on other sites More sharing options...
ArtZ Posted October 28, 2009 Author Share #74 Posted October 28, 2009 Thank you Sandy. I'm following this issue with a lot of attention. I'd love to use wide angle lenses at their nominal focal length on a digital M. That will be for me the main reason to upgrade from the M8. Link to post Share on other sites More sharing options...
SJP Posted October 30, 2009 Share #75 Posted October 30, 2009 While the asymmetry can be dealt with via cornerfix I am really puzzled by this effect. The only possible cause of such asymmetry, I believe, would be an unevenness in the microlens alignment with respect to the sensor CCD pixels. I do not see how the sensor & lens as such could be out of alignment, assuming that Leica knew what they were doing at the design stage. M lenses should have axially symmetric vignetting etc. so that can't be the explanation. Link to post Share on other sites More sharing options...
Alejandro1 Posted October 30, 2009 Share #76 Posted October 30, 2009 I understand that there's a problem with the M9. Some photographs comes out with a (green?) line in the middle. How serious it's? I don't know, but it could be important enough, so as to have Leica pull out every M9 from the shelf and recalling the few that were sold and stop delivering the M9 until further notice. Link to post Share on other sites More sharing options...
stunsworth Posted October 30, 2009 Share #77 Posted October 30, 2009 ...it could be important enough, so as to have Leica pull out every M9 from the shelf and recalling the few that were sold and stop delivering the M9 until further notice. The only problem with your theory is that Leica haven't recalled any cameras, are still supplying them to dealers, and the dealers are still selling every one they can get their hands on. Link to post Share on other sites More sharing options...
andybarton Posted October 30, 2009 Share #78 Posted October 30, 2009 Frankly I think suggesting a potential hardware issue is pretty irresponsible and damaging to Leica as they try to get their business on a sound business footing. I hope unless there is something concrete to report that people do not add to the malicious speculation and rumours. It is however heart warming, and I feel vindicated to see some people now suggesting that M9 is a stop gap camera .... These same people attacked me for stating that I planned to wait until the M10 arrives (10/10/10). I seem to remember being told that M9 is the end of the line and that Stefan had said so in the video (which he did not by the way!). Is it not also true that continually stating that 10/10/10 is the launch date for the currently non-existent M10 is also irresponsible? Link to post Share on other sites More sharing options...
Guest BigSplash Posted October 30, 2009 Share #79 Posted October 30, 2009 Is it not also true that continually stating that 10/10/10 is the launch date for the currently non-existent M10 is also irresponsible? Yes if people believe that any of us on ths forum have knowledge today of a M10 being released at any date. To avoid any doubt I have repeatedly said I have NO, absolutely NO knowledge of a M10. That said I am of the very firm opinion that there wil be a M10 and as stated in other threads I have suggested that: Leica Solms should hopefully be working on it NOW, since a few months. Commercially and probably technically they need it in my opinion by end 2010 At a business level it will be interesting to see the next annual results (March 2010?..or possibly later as happened in 2009). Then we shall all see how the P&L looks at that time and if M9, S2, X1 and Pradovit plus new lenses etc have taken Leica out of the red and hugely positive. ..My guess is that all this will have impact on the M10 release, quite apart from technical considerations I think it is not irresponsible at all to state the above on a forum like this. I think it is very irresponsible to suggest that the M9 is somehow flawed, and those niggles that we are aware of cannot be corrected by a simple firmware fix. I feel that Leica are doing themselves no favours by not communicating firmware fix release dates for the several known problems that they admit to. Currently we have a situation that there are threads that suggest for example: 18mm lens vis a vis the sensor may have a mechanical misalignment issue...others suggest that this is a simple firmware fix to resolve. Shutter lock up issue remains on M8 and M9 since months and is well known Red line issue Camera lock up if bottom plate is removed Other...there is a long list! I am surprised that Leica does not announce for its flagship product how it will address these issues in the short term. That said I believe that the camera is far from flawed, however the longer Leica remain quiet I think Leica itself as a company is not doing a good marketing job ...especially after successfully stimulating a market and then NOT delivering against : A hugely delinquent backlog, and unhappy, unfulfilled client base. The situation seems to be unresolved for many months. A less than 100% product perfect performance for a camera that costs a mighty £4850 for a camera body. Link to post Share on other sites More sharing options...
andybarton Posted October 30, 2009 Share #80 Posted October 30, 2009 What makes you think that Leica aren't already dealing with the issues that have arisen with the M9 since its launch? You should know by now that Leica are not a very communicative company. Best to let them get on with what they are doing, IMHO. I am sure that they are very well aware of what all the issues are. Link to post Share on other sites More sharing options...
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