mmradman Posted October 17, 2016 Share #21 Posted October 17, 2016 Advertisement (gone after registration) After furthet enquiring, Leica wrote me that they don't have a technical explanation. This is the second let down I am getting from them and I am starting to look some where else. I also reflected on the possibility that the problem could be caused by sensor heating but to me that's unlikely, as I had the same problem in Hokkaido, in Jannuary, with -30. Just a suggestion, a person with "Leica bashing" reputation is Lloyd Chambers or Digilloyd, it may be worthwhile having a conversation with him. When M246 was launched he was the one who picked up some anomalies to some derision from Leica community. https://diglloyd.com/ https://diglloyd.com/blog/2015/20151002_1138-LeicaM_Monochrom-BlackDotInWhiteSpotArtifacts-update.html Quote Link to post Share on other sites More sharing options...
Advertisement Posted October 17, 2016 Posted October 17, 2016 Hi mmradman, Take a look here Long exposures problems with typ 246. I'm sure you'll find what you were looking for!
pop Posted October 17, 2016 Share #22 Posted October 17, 2016 Yes, exactly, it's pitch black and there is no transition, some time it happens in other parts of the frame I don't understand what you mean by there being no transition. I applied the ImageAnalyzer (a nice little shareware program) to the lower right corner of your photograph. This is the part of your image I analyzed. It's, of course, the lower right corner: 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! This is the brightness profile along the diagonal which runs from the top left corner of the selected part of the image to the lower right corner: As you can clearly see, the body of water is a darkish gray close to the center of the image and then becomes progressively darker towards the corner of the image, until the brightness value reaches zero. I wonder how those values progress in the DNG file. Sorry about the scaling of the diagram. The width of the diagram shows the brightness along the entire diagonal of the squarish crop. Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! This is the brightness profile along the diagonal which runs from the top left corner of the selected part of the image to the lower right corner: As you can clearly see, the body of water is a darkish gray close to the center of the image and then becomes progressively darker towards the corner of the image, until the brightness value reaches zero. I wonder how those values progress in the DNG file. Sorry about the scaling of the diagram. The width of the diagram shows the brightness along the entire diagonal of the squarish crop. ' data-webShareUrl='https://www.l-camera-forum.com/topic/265185-long-exposures-problems-with-typ-246/?do=findComment&comment=3130134'>More sharing options...
pop Posted October 17, 2016 Share #23 Posted October 17, 2016 Here's another way of looking at the problem: 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! The brightest part is about in the middle of the image. It then continually grows darker towards the corners. The lower right corner is merely underexposed, it seems. 1 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! The brightest part is about in the middle of the image. It then continually grows darker towards the corners. The lower right corner is merely underexposed, it seems. ' data-webShareUrl='https://www.l-camera-forum.com/topic/265185-long-exposures-problems-with-typ-246/?do=findComment&comment=3130150'>More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #24 Posted October 17, 2016 (edited) Here's another way of looking at the problem: post-1373-0-90077200-1475513513.jpg The brightest part is about in the middle of the image. It then continually grows darker towards the corners. The lower right corner is merely underexposed, it seems. It is underexposed for no reason as it has the same brightness of the left corner as shown in the other image that I posted above, which only difference is not to be a long exposures. If you read through the thread you would see that, with long exposures, the problem happens also in other parts of the frame, always at borders or corners. Often is in the form of a moustache starting from the middles of the right border, pitch black. I'll try to repeat the problem and post other pictures to convince the Leica advocates. Edited October 17, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
jaapv Posted October 17, 2016 Share #25 Posted October 17, 2016 Thanks pop, so it is simple shadow clipping. Well Leica offers clipping warnings on the LCD. Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #26 Posted October 17, 2016 (edited) Thanks pop, so it is simple shadow clipping. Well Leica offers clipping warnings on the LCD. Shadow clipping for no reason Edited October 17, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
pop Posted October 17, 2016 Share #27 Posted October 17, 2016 Advertisement (gone after registration) It is underexposed for no reason as it has the same brightness of the left corner as shown in the other image that I posted above, which only difference is not to be a long exposures. .... I measured the brightness value in the second photograph (the lighter one). The water close to to the bottom right corner has the value 60 +/- 2; the water close to the bottom left corner has the value 75 +/- 3. They do not have the same brightness. The bottom right corner in the first picture is underexposed. There is no dark blob without transition. The transition is there and it's very smooth. Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #28 Posted October 17, 2016 (edited) I measured the brightness value in the second photograph (the lighter one). The water close to to the bottom right corner has the value 60 +/- 2; the water close to the bottom left corner has the value 75 +/- 3. They do not have the same brightness. The bottom right corner in the first picture is underexposed. There is no dark blob without transition. The transition is there and it's very smooth. The difference in light between the two corners does not justify a pitch black corner. On my book, which is pretty big, the transition on the right corner is not at all smooth. I think that by blindly refusing to aknowledge the problem you are not doing any good to your brand. I'll post other examples and then you'll tell me about it. Edited October 17, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
pop Posted October 17, 2016 Share #29 Posted October 17, 2016 The minimal difference in light between the two corners does not justify a pitch black corner. I think that by blindly refusing to aknowledge the problem you are not doing any good to your brand. I'll post other examples and then you'll tell me about it. It is not "my" brand. I am a member here just as you are. The forum is not owned by Leica. I have carefully shown in my first post how the picture grows darker in a very orderly and regular fashion until the brightness value reaches zero which is the value for pitch black. Digital images can not become any darker than that. I also pointed out that the DNG could show a different behaviour. This is because the DNG format can differentiate more values. If you find my material difficult to follow, I'm sorry. Don't bother to produce more pictures for me as I won't look at them. Your picture is underexposed. 1 Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #30 Posted October 17, 2016 1) Don't bother to produce more pictures for me as I won't look at them. 2) Your picture is underexposed. 1) Yes please as you are not very helpful. 2) The right corner of my picture is underxposed, for no reasons. Quote Link to post Share on other sites More sharing options...
jaapv Posted October 17, 2016 Share #31 Posted October 17, 2016 Shadow clipping for no reasonShadow clipping by underexposure. Use the clipping warnings the camera provides. Eyeballing exposure is imprecise at best. Thanks for that analyzing program, Philipp, it is far more practical to use than measuring in Photoshop. Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #32 Posted October 17, 2016 (edited) Shadow clipping by underexposed. Use the clipping warnings the camera provides. Only the right corner comes out as underexposed and the minimal difference in brightness between the two corners does not justify it 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 October 17, 2016 by Giulio Zanni 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/265185-long-exposures-problems-with-typ-246/?do=findComment&comment=3130214'>More sharing options...
pop Posted October 17, 2016 Share #33 Posted October 17, 2016 Did you look at the DNG? Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #34 Posted October 17, 2016 (edited) Did you look at the DNG? Yes, these are all unedited jpegs from unedited DNGs. I use a Eizo 30" calibrated monitor and I can see very well what is going on Edited October 17, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
jaapv Posted October 17, 2016 Share #35 Posted October 17, 2016 Only the right corner comes out as underexposed and the minimal difference in brightness between the two corners does not justify it That only proves that the water is deeper thus darker on the righthand side. In the lower left corner you can even see the bright sandy bottom. There is clearly a considerable difference in brightness which your camera recorded correctly. Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 17, 2016 Author Share #36 Posted October 17, 2016 (edited) That only proves that the water is deeper thus darker on the righthand side. In the lower left corner you can even see the bright sandy bottom. There is clearly a considerable difference in brightness which your camera recorded correctly. No it didn't, it recoded the right corner much, much, much darker that it should have had. We can go on with this forever but I am not buying it. I have 40 years of photography on my back, several camera systems from film to digital and several international awards. You can rest assure that there is something wrong in these files. I'll post more examples. By the way, have you ever done a long exposure (between 30 and 60 sec) with your M 240? Edited October 17, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
pop Posted October 17, 2016 Share #37 Posted October 17, 2016 I think you could compare the two images which you posted here much easier if you processed them in the same way. One picture (the one with the 1/500 exposure) has a lens profile applied and the exposure has been corrected by +1.25 (unit unknown to me). The other one (with the 9" exposure) has no lens profile applied and the exposure has been corrected by -0.85. When I adjust the brightness and contrast of the picture with the short exposure such that the rocks and the bunker in the foreground and the landmass in the background look about the same and then add some artificial vignette, the bottom right corner looks about the same, too, with a pitch black area of roughly the same size. The conclusion I reach is that the contrast of the photograph is greater than what can be expressed in a JPEG file, being confined to a depth of 8 bits. I still suspect that the dark corner could be recovered from the DNG. Quote Link to post Share on other sites More sharing options...
250swb Posted October 18, 2016 Share #38 Posted October 18, 2016 (edited) Blaming the camera is getting wearisome, has anybody considered the cause to be reflected or refracted polarised light at the waters surface? It is the reason why fishermen wear polaroid glasses, otherwise they can't see into the water, perhaps the camera can't see into the water either. It is also a sunny day, any chance the OP was seeing something that the camera can't see? The reflection or refraction at the waters surface will change with distance and angle, and given the darker areas in question are at the bottom of the image it could just be the effect expected. As polarised light filters out or re-orients the different wavelengths perhaps the Monochrom can't record the same spectrum that the eye can see...........................???? Technically there are a lot of things that may cause one photograph to show the effect of polarised light and another not, a change in the breeze causing a different wave pattern, aperture, length of exposure, a cloud passing, ten minutes for the sun to move in the sky, etc. Steve Edited October 18, 2016 by 250swb 1 Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 18, 2016 Author Share #39 Posted October 18, 2016 (edited) I think you could compare the two images which you posted here much easier if you processed them in the same way. One picture (the one with the 1/500 exposure) has a lens profile applied and the exposure has been corrected by +1.25 (unit unknown to me). The other one (with the 9" exposure) has no lens profile applied and the exposure has been corrected by -0.85. When I adjust the brightness and contrast of the picture with the short exposure such that the rocks and the bunker in the foreground and the landmass in the background look about the same and then add some artificial vignette, the bottom right corner looks about the same, too, with a pitch black area of roughly the same size. The conclusion I reach is that the contrast of the photograph is greater than what can be expressed in a JPEG file, being confined to a depth of 8 bits. I still suspect that the dark corner could be recovered from the DNG. These are unedited jpegs, maybe the only thing I could have doen was to recover few blinkies on the bunker. They were both shot with the same lens. You look at jpegs because I can not post DNGs on the forum but the DNG looks exactly the same. It's not a jpeg problem as I shoot in DNG only. Whether the dark corner could be recover or not is a total different matter. It shouldn't be there. Edited October 18, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
Giulio Zanni Posted October 18, 2016 Author Share #40 Posted October 18, 2016 (edited) Blaming the camera is getting wearisome, has anybody considered the cause to be reflected or refracted polarised light at the waters surface? It is the reason why fishermen wear polaroid glasses, otherwise they can't see into the water, perhaps the camera can't see into the water either. It is also a sunny day, any chance the OP was seeing something that the camera can't see? The reflection or refraction at the waters surface will change with distance and angle, and given the darker areas in question are at the bottom of the image it could just be the effect expected. As polarised light filters out or re-orients the different wavelengths perhaps the Monochrom can't record the same spectrum that the eye can see...........................???? Technically there are a lot of things that may cause one photograph to show the effect of polarised light and another not, a change in the breeze causing a different wave pattern, aperture, length of exposure, a cloud passing, ten minutes for the sun to move in the sky, etc. Steve If you read through the thread you would have noticed that the problem is not limited to this image,but it happens also in images with no water. I just regret I didn't keep all those bad images but I will be out again during the week-end and I am sure that the problem will come up again as it has happened before. Edited October 18, 2016 by Giulio Zanni Quote Link to post Share on other sites More sharing options...
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