fotomas Posted June 5, 2014 Share #1 Posted June 5, 2014 Advertisement (gone after registration) Hello, took a few pictures today with my M 240. Now I discovered an very ugly image failure. There was a window band, where the sun comes in and it went through the man in the middle. Has anyone made the same experience and how this issue is named? It turned out clear to see when I lit the picture up, but it is also visible in the original, the darker one, that I underexposed a bit to save the highlights. Is there something one could do to avoid this? (Maybe I should went back to film:eek:) 1250 ASA, Cron 35 ASPH, f 3.4, 1/250. 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! Original exposure f-( Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! Original exposure f-( ' data-webShareUrl='https://www.l-camera-forum.com/topic/228412-sensor-flare/?do=findComment&comment=2604867'>More sharing options...
Advertisement Posted June 5, 2014 Posted June 5, 2014 Hi fotomas, Take a look here Sensor flare?. I'm sure you'll find what you were looking for!
jaapv Posted June 5, 2014 Share #2 Posted June 5, 2014 Yes, it seems quite normal to me. With such a massive contrast overload I would have expected worse - with any sensor. Link to post Share on other sites More sharing options...
fotomas Posted June 5, 2014 Author Share #3 Posted June 5, 2014 Thanks! I have had the hope the had fixed this until today. Therefore I stayed with film for so long... Link to post Share on other sites More sharing options...
jaapv Posted June 5, 2014 Share #4 Posted June 5, 2014 Film has its own problems, and so have all technologies. Actually the band on the jacket would not worry me at all, that is the simplest of things to fix in postprocesing. I would be more worried about the loss of detail in the latticework at the right, although there is probably a bit to be recovered. If I would have taken the shot I would have been at base ISO, underexposed (relative to your exposure) by at least two more stops and pulled up the shadows, or even done a double develop and layer mask. In PS CC the HDR toolbox would do a fine job too. Link to post Share on other sites More sharing options...
John Black Posted June 6, 2014 Share #5 Posted June 6, 2014 If the 100% crop has organic edges, meaning it follows the lay of the jacket fabric, and depending on the edges look between the bright areas and dark jacket, this could be some type of sensor bloom and/or optical anomaly (high contrast edges). More interesting is the ISO 1250, which means gain has been applied - either software based or electronically via the camera's circuits. This is more suspect than optical causes. Other things to consider would be whether live view or the EVF was used - that heats up the sensor and can cause similar artifacts. Another possible culprit is the read/write error to the SDHC card. Less common, but I've had this happen with oncoming headlights and such - the light reflects off the sensor, back onto the lens, back onto the sensor. The visible result in the captured image was double edged highlights. This was more of a problem with the M9 (for me). Really need to see a 100% crop of the offending area to judge how digital the artifacts look vs optical anomaly. Link to post Share on other sites More sharing options...
mjh Posted June 6, 2014 Share #6 Posted June 6, 2014 One thing is certain: this is not blooming. Blooming occurs when more electrons are generated than a pixel can hold, so the excess charge spills over to neighbouring pixels. Often these pixels cannot store any more electrons either so the spill continues until it reaches a darker area. A number of pixels may be required to take up the excess charge but once the charge accumulated by a pixel stays below 100 percent the wave stops – end of blooming. So whenever there is blooming we expect to find a sharply defined area of clipped pixels at 100 percent. What we have here, however, is a faint magenta stripe in a relatively dark area – the man’s back. This cannot be blooming, even when there may be blooming to the left and right of the magenta area. Given the perfect alignment with the bright stripe it looks like a sensor, not a lens phenomenon. I would have a suspected an issue with the reference pixels outside the sensor’s active imaging area, but then the bright stripe does not extend all the way to the left. Maybe some correction mechanism has been thrown off by the high percentage of clipped pixels in the same row. Link to post Share on other sites More sharing options...
fotomas Posted June 6, 2014 Author Share #7 Posted June 6, 2014 Advertisement (gone after registration) Thanks for your answers so far! Really need to see a 100% crop of the offending area to judge how digital the artifacts look vs optical anomaly. Here they are: Crop 1, JPEG quality setting 11 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! Crop 2 JPEG quality setting 12 (best) I like to do some test today at the same location, if this somehow is possible. Sun is shinning today also. But I'm afraid the elevating platform won't be there any more. The person is also gone. So I have to try to find some similar setup. Frank Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! Crop 2 JPEG quality setting 12 (best) I like to do some test today at the same location, if this somehow is possible. Sun is shinning today also. But I'm afraid the elevating platform won't be there any more. The person is also gone. So I have to try to find some similar setup. Frank ' data-webShareUrl='https://www.l-camera-forum.com/topic/228412-sensor-flare/?do=findComment&comment=2605147'>More sharing options...
mjh Posted June 6, 2014 Share #8 Posted June 6, 2014 Crop 2 suggests some blooming on the right side; this would explain why parts of the lattice are gone. But the blooming stops at the right sleeve; the magenta stripe is a different issue not directly related to blooming. Link to post Share on other sites More sharing options...
John Black Posted June 6, 2014 Share #9 Posted June 6, 2014 Did a quick extreme levels edit just to see the character of the band. It's a gradual edge, so it doesn't look like a SDHC read/write error. It looks like the pixels were influenced by some type of sensor blooming at the edge of jacket sleeve. I suspect ISO 1250 played a role in that. That said, boosting this required an extreme levels edit. The effected area is barely visible in the unedited JPEG. So, I'd chalk this up to - "this is what can happen at upper ISOs with a high contrast edge". If this was a ISO 200 DNG, I'd might be concerned, but not at ISO 1250. 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/228412-sensor-flare/?do=findComment&comment=2605189'>More sharing options...
kdriceman Posted June 6, 2014 Share #10 Posted June 6, 2014 The magenta stripe in unusual and I don't understand why it is occurring. As Michael says, it's not blooming. Is this from an in-camera jpeg? I wonder if it is related to in camera processing of the jpeg. I did not think The M240 applied much noise reduction at 1250 to raw files but maybe to JPEGs and perhaps it is associated with that. I would try it with DNG and an external raw convertor and/or, as Jaap says lower ISO and pull up the shadows to see if it does it again. Link to post Share on other sites More sharing options...
Hookeye Posted June 6, 2014 Share #11 Posted June 6, 2014 Hmm.. this makes me think of the infamous "green stripe" we sometimes see with the M8 with a strong light source just outside the image field. While it tickles my curiosity and I would like to understand "why", I would not worry about it unless it is a consistent problem and not one that crops up in (very) special situations. Link to post Share on other sites More sharing options...
jaapv Posted June 6, 2014 Share #12 Posted June 6, 2014 Did a quick extreme levels edit just to see the character of the band. It's a gradual edge, so it doesn't look like a SDHC read/write error. It looks like the pixels were influenced by some type of sensor blooming at the edge of jacket sleeve. I suspect ISO 1250 played a role in that. That said, boosting this required an extreme levels edit. The effected area is barely visible in the unedited JPEG. So, I'd chalk this up to - "this is what can happen at upper ISOs with a high contrast edge". If this was a ISO 200 DNG, I'd might be concerned, but not at ISO 1250. Not high ISO; high contrast. The sensor’s anti-blooming gates are overloaded by a too high photon load. On the magenta stripe I have no opinion, just an idea. Failure of the raw conversion. Try another converter and see what happens. Link to post Share on other sites More sharing options...
fotomas Posted June 6, 2014 Author Share #13 Posted June 6, 2014 Is this from an in-camera jpeg? No. I only shoot RAW. The 100% crops are developed in C1 v7.1.6 as 16 bit TIFF with camera-profile attached. Then converted as JPEG for the web with PS CS4. Link to post Share on other sites More sharing options...
fotomas Posted June 7, 2014 Author Share #14 Posted June 7, 2014 Hello, now I've made some test to figure out if there is a way to get around the problem. Here the test setup with different ISO settings. I underexposed the pictures about 1,5 to 2 f-stops to save the highlights as much as possible. Therefor the shadows have to be brighten up strongly in C1, what will make the effect more visible. The last picture is exposed to a similar brightness in the camera. 1250 ISO 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! 800 ISO 400 ISO 200 ISO 200 ISO exposed to the final brightness Looked like the only way to avoid this or to minimize this is to go to 200 ISO. Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 800 ISO 400 ISO 200 ISO 200 ISO exposed to the final brightness Looked like the only way to avoid this or to minimize this is to go to 200 ISO. ' data-webShareUrl='https://www.l-camera-forum.com/topic/228412-sensor-flare/?do=findComment&comment=2606122'>More sharing options...
fotomas Posted June 7, 2014 Author Share #15 Posted June 7, 2014 Here a comparison with some other cameras at 1250 ISO to proof if it's a global sensor phenomenon. The Nikons are equipped with a Zeiss 35/2,0 lens at f2,8. Leica M240 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! Nikon D700 Nikon D800 Nikon D3X In the end the Leica M again at 3200 ISO not brighten up to show the original level of exposure. Couldn't find the phenomenon at the Nikons. Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! Nikon D700 Nikon D800 Nikon D3X In the end the Leica M again at 3200 ISO not brighten up to show the original level of exposure. Couldn't find the phenomenon at the Nikons. ' data-webShareUrl='https://www.l-camera-forum.com/topic/228412-sensor-flare/?do=findComment&comment=2606128'>More sharing options...
fotomas Posted June 7, 2014 Author Share #16 Posted June 7, 2014 Here some 100% crops at 1250 ISO. Not always really 100 %. I sized all files down to the pixel of the D700 that has the smallest pixel-count, just to make them comparable. M240 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! D700 D800 D3X Here the M240 at 200 ISO Even here you can see a trace. Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! D700 D800 D3X Here the M240 at 200 ISO Even here you can see a trace. ' data-webShareUrl='https://www.l-camera-forum.com/topic/228412-sensor-flare/?do=findComment&comment=2606139'>More sharing options...
pico Posted June 7, 2014 Share #17 Posted June 7, 2014 Do you have a filter in front of the lens? Link to post Share on other sites More sharing options...
fotomas Posted June 8, 2014 Author Share #18 Posted June 8, 2014 Do you have a filter in front of the lens? No. Link to post Share on other sites More sharing options...
fotomas Posted June 12, 2014 Author Share #19 Posted June 12, 2014 What I like to know: is someone able to reproduce this behavior, or is it just my M240? Cheers Frank Link to post Share on other sites More sharing options...
Exodies Posted June 12, 2014 Share #20 Posted June 12, 2014 This is a very difficult picture to look at. I took the attached picture looking out of my window into the morning sunny sky, M typ 240, APO-Summicron M 1:2/50 ASPH. (to avoid the wrath of those with ad-hoc-abbreviation phobias), one stop over spot metered exposure (spot on the dark bar). ISO 200, 350th, f4. No filter, hand held, 2.0.0.12 firmware version (yes, that old thing). In Lightroom I can only see things which are actually in the scene but in the exported, reduced JPEG, I'm not sure whether the bright stripe affects the dark vertical. My eyes don't like this much contrast. Can anyone else see corruption? The second image (see next post due to incompetence) is cropped in Lightroom, full size exported, reduced in Apple preview. I don't see anything in the dark vertical which isn't in the scene. For me, the camera is ok, but I have doubts about the Lightroom export for email followed by Preview reduction when there is a large white band. (The reduction in Preview step was the result of a brain fart, sorry for this unnecessary complication) 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/228412-sensor-flare/?do=findComment&comment=2609100'>More sharing options...
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