ho_co Posted August 25, 2007 Share #21 Posted August 25, 2007 Advertisement (gone after registration) Does the M8 not have the facility to map out hot pixels, either automatically as other top-tier digitals, or through a menu-accesible sub-routine as does the updated Epson RD1-s? No, at least not yet. Perhaps it could be added to later firmware. Good point. At least some of those 'other top-tier digitals,' as you call them, require the use of their software to take advantage of the mapping facility; and in some cases, that software must be bought separately from the camera. Something of an affront, don't you think, to have to pay for software to cover up something you shouldn't have? Just in general, isn't it an interesting concept to establish an in-camera routine to map out hot pixels? I understand the practicality of doing that, but wouldn't you prefer having no hot pixels to having a map of them? "O brave new world, that hath such concepts in't." --HC Link to post Share on other sites More sharing options...
Advertisement Posted August 25, 2007 Posted August 25, 2007 Hi ho_co, Take a look here M8, dead pixels, dust and other nasty things. I'm sure you'll find what you were looking for!
carstenw Posted August 25, 2007 Share #22 Posted August 25, 2007 It's dust in the lens. Shoot the same picture stopped down and then do another one all the way open and you'll see the dust specs disappear. The ones that are still there are either sensor dust or bad pixels. Garin, the same effect exactly also hides dust on the sensor. It is more likely to be on the sensor, because no matter how close the rays are focused on the lens, the trip to the sensor is still relatively large. The small aperture just ensures that the light doesn't land on the sensor from all directions, but arrive from just one, thus casting a proper shadow. Link to post Share on other sites More sharing options...
adan Posted August 25, 2007 Share #23 Posted August 25, 2007 1) hot/stuck pixels are the opposite of dead pixels: the first put out too much signal which shows as a bright spot, or sometimes a +-shaped spot (since in de-bayerizing their signal influences the surrounding pixels); the latter would be black (dead, no signal) - and are more common in LCDs than in CCD/CMOS sensors. I've only had stuck pixels in the M8, and only a very few, and none have stayed permanently - yet. My RD-1 had about 30 stuck pixels at ISO 1600 by the time it was 6 months old. I'm going out tonight to shoot some rural dirt-track racing - a real acid test for low light/high-ISO artifacts, so I should have some fresh samples of how the M8s are behaving now. 2) As to the vertical line - I have yet to see an M8 (and have shot with 7-8 at varrious times) that does NOT pop this up occasionally. Depends on the light level, the ISO, and even the color temp. - in some tungsten shots it is clearly more obvious in the poor underexposed blue channel. Also for some reason it seems to be more obvious in jpegs (which smooth out the more random noise) than in RAW, where the random noise may mask the hard line. 3) Dust on the lens (or scratches, for that matter) WILL NOT show up in the image EVER - except in bright out-of-focus blur circles, where it/they will get imaged just the same as the aperture blades. Dust on the sensor will vary in "sharpness" with aperture, or with the focal length of the lens - e.g. my 135 often reveals dust even at f/4 because the lens is so long that the "window" of light is very vertical to the image plane, casting a sharper edge to any sensor dust bunnies. Link to post Share on other sites More sharing options...
Nitnaros Posted August 26, 2007 Share #24 Posted August 26, 2007 2) As to the vertical line - I have yet to see an M8 (and have shot with 7-8 at varrious times) that does NOT pop this up occasionally. . I had a different experience; the vertical line starting popping up in all shots at a certain point in time. I checked earlier shots, they did not show it. A vertical line of faulty pixel is a harware failure. My M8 got replaced by Leica NJ. Peter Link to post Share on other sites More sharing options...
Guest Walt Posted August 26, 2007 Share #25 Posted August 26, 2007 I had a different experience; the vertical line starting popping up in all shots at a certain point in time. I checked earlier shots, they did not show it. A vertical line of faulty pixel is a harware failure. My M8 got replaced by Leica NJ. Peter Yes, the same experience. Walt Link to post Share on other sites More sharing options...
guy Posted August 26, 2007 Share #26 Posted August 26, 2007 You should know how to clean your sensor if you're going to freak out about every tiny dot in your images. It's part of owning any digital camera. I think people can be a little too hysterical for their own good about these things. Umm... that's helpful. Link to post Share on other sites More sharing options...
Guest sirvine Posted August 26, 2007 Share #27 Posted August 26, 2007 Advertisement (gone after registration) Feel free to pay someone to clean your sensor, or send your camera in to Leica for service. I haven't seen anything in the OP's images that looks like anything more than standard operator error. And plenty of manufacturers ship with dust on the sensor. I'll leave this thread to the hand-wringers. Link to post Share on other sites More sharing options...
Leicamateur Posted August 26, 2007 Author Share #28 Posted August 26, 2007 How is it the opperator's error if there is a vertical line of dead or whatever pixels? If you don't intend to help but insult other people you better leave sirvine, I really don't need this. However, I made more test shots today and with ISO 1250 and ISO 2500 settings the vertical line always shows at the same place. So I'll definitely contact Leica on Monday to get a replacement. As for the dust on sensor (no its not dust on / in lens, lenses are perfectly clean) this is a total different matter on not the main point here. I'm wondering how Leica will react to this problem. 100% crop, ISO 2500 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! 100% crop, ISO 1250 Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 100% crop, ISO 1250 ' data-webShareUrl='https://www.l-camera-forum.com/topic/31868-m8-dead-pixels-dust-and-other-nasty-things/?do=findComment&comment=338398'>More sharing options...
jaapv Posted August 26, 2007 Share #29 Posted August 26, 2007 I'm not sure this is a dead pixel; it seems one pixel overloads so much in the red channel that a whole row is affected. (If this makes sense..??) Link to post Share on other sites More sharing options...
Guest sirvine Posted August 26, 2007 Share #30 Posted August 26, 2007 How about cleaning the sensor, and if the vertical line problem (documented ad nausuem on this site) persists, replace it? I don't know how anyone could diagnose the problem from those test shots, esp. until the sensor has been cleaned. BTW, even NASA has dirty sensors: http://chamorrobible.org/images/photos/gpw-20061021-NASA-ISS015-E-23716-space-huge-clouds-Earth-20070820-medium.jpg I wonder if they complain about paying a premium, etc. Link to post Share on other sites More sharing options...
Leicamateur Posted August 26, 2007 Author Share #31 Posted August 26, 2007 If you use the search function you will found lots of other posts describing the same problem. It's apparently a hardware fault else Leica wouldn't replace M8s with this problem. Link to post Share on other sites More sharing options...
Guest tummydoc Posted August 26, 2007 Share #32 Posted August 26, 2007 No, at least not yet. Perhaps it could be added to later firmware. Good point. At least some of those 'other top-tier digitals,' as you call them, require the use of their software to take advantage of the mapping facility; and in some cases, that software must be bought separately from the camera. Something of an affront, don't you think, to have to pay for software to cover up something you shouldn't have? Less of an affront that having to pay shipping/insurance and wait weeks or months for it to be sorted? I daresay, no. Just in general, isn't it an interesting concept to establish an in-camera routine to map out hot pixels? I understand the practicality of doing that, but wouldn't you prefer having no hot pixels to having a map of them? Yes of course, however I strongly suspect that if the issue is <dozen random hot pixels, all that will be done in a service is mapping-out. If there is indeed a row of dead pixels then in that case perhaps they will exchange the sensor. Link to post Share on other sites More sharing options...
Philip Freedman Posted August 27, 2007 Share #33 Posted August 27, 2007 The problem of dust or dead pixels on an M8 sensor is probably, in most cases, less annoying than dust and grain on 35mm film. I recently took two shots of the house opposite mine - about 300 yards away - one with my M8 at ISO 160 with newish 35mm lens, RAW processed with Capture One and saved as a TIFF and the other with an old M3 with an old 50 mm lens and XP2 processed at our local fast process shop and scanned as a TIFF with Vuescan on my 5400. When viewed highly enlarged on my PC to the same size, both show high contrast features (eg TV aerial against the sky) quite clearly but lower contrast elements such as the roof tiles and bricks of the house, whilst clearly seen on the scanned negative, are smeary in the M8 photo and lacking in detail . However, the scanned negative shows lots of dust spots and grain whereas the M8 photo is (fortunately) dustfree and 'cleaner' - grainless (until you enlarge it to pixellation). Life is such a compromise! Philip Link to post Share on other sites More sharing options...
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