davichan Posted August 30, 2007 Share #1 Posted August 30, 2007 Advertisement (gone after registration) i am asumming this is M8 moiree, I use lightroom for my files. M8, 35 sumilux ASPH at possibly f5.6 this just camera RAW file, no post work made. quick photoshop 100% crop along with overview jpegs to show. I have tried to blur the B channel in LaB mode in Photoshop. and also the apply image trick: http://unsharp-mask.blogspot.com/2007/08/moir-removal-in-photoshop.html but they dont seem to work. any leads or comments on how to fix this. love to hear what the gang here thinks. thank you all for any time. -dav 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/32287-m8-moiree-kills-pictures/?do=findComment&comment=342416'>More sharing options...
Advertisement Posted August 30, 2007 Posted August 30, 2007 Hi davichan, Take a look here m8 moiree, kills pictures.. I'm sure you'll find what you were looking for!
Shootist Posted August 30, 2007 Share #2 Posted August 30, 2007 Looks like the sensor, or the image processor, got confused as to what was in that window. Doesn't really look like moire. Have you tried cloning the other windows into that area. Could be you have a bad sensor. Be chance was the sun glaring off that window. I have seen this maze pattern when taking shots with the sun in it. Link to post Share on other sites More sharing options...
rbaron Posted August 30, 2007 Share #3 Posted August 30, 2007 Is this an isolated instance or do you have more / many shots with the same issue? Link to post Share on other sites More sharing options...
jonoslack Posted August 30, 2007 Share #4 Posted August 30, 2007 I think it's a faulty sensor I've seen something similar in about 5 shots (out of 10,000) in extremely high contrast areas - I don't think you should see it like that. Back to your dealer I'd say. Link to post Share on other sites More sharing options...
teehas53 Posted August 30, 2007 Share #5 Posted August 30, 2007 Looks like the sensor, or the image processor, got confused as to what was in that window. Doesn't really look like moire... Could be you have a bad sensor... It is a kind of pattern interference, if not technically moire in the same sense as we sometimes experience with fabrics, etc. I've seen it too occasionally. Nothing wrong with your camera or sensor, just another by-product of the weak AA filter in the M8. Creative post production is the only real solution... T Link to post Share on other sites More sharing options...
gravastar Posted August 30, 2007 Share #6 Posted August 30, 2007 It is a kind of pattern interference, if not technically moire in the same sense as we sometimes experience with fabrics, etc. I've seen it too occasionally. Nothing wrong with your camera or sensor, just another by-product of the weak AA filter in the M8. Creative post production is the only real solution... T Yes, it's a form of moire and in places mosaicing/mazeing due to the Bayer algorithms. Both Canon 1Ds and 1Ds MkII cameras I've used have shown almost identical patterns at times. Usually selectively blurring chroma channels in LAB mode helps but when there's a strong luminance component as well it's much more difficult to correct in post without losing detail. Bob. Link to post Share on other sites More sharing options...
Jamie Roberts Posted August 30, 2007 Share #7 Posted August 30, 2007 Advertisement (gone after registration) I'm with Jono and Ed here--I've never seen anything like that in normal contrast and exposure levels. I'd have it back to the dealer, with the shot. Link to post Share on other sites More sharing options...
wattsy Posted August 30, 2007 Share #8 Posted August 30, 2007 The maze-like pattern is definitely moire related - and I see it occasionally in some of my files (from both cameras) but I have never seen it as severe as this. Personally, I find even the very mild cases to be a major annoyance because it has to be cleaned up in files for stock submission. I raised the matter with the M8 customer services and they rather unhelpfully suggested I should up the noise suppression slider in C1 (which does reduce the problem but only at the expense of the loss of detail). Link to post Share on other sites More sharing options...
gravastar Posted August 30, 2007 Share #9 Posted August 30, 2007 Here's what happens if you convert the image to Lab mode, select the colored area and blur the a and b channels. You then have to select a brightness range within the L channel and carefully adjust the brightness in an attempt to minimise the visibility of the luminance patterning. I didn't do a very good job of the last step - but you get the idea. Bob. 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/32287-m8-moiree-kills-pictures/?do=findComment&comment=342524'>More sharing options...
iridium7777 Posted August 30, 2007 Share #10 Posted August 30, 2007 whoah, that's awesome. it's like the matrix broke down or something. seriously, that's really cool, you can make out some sort of a curcuit. unless it was a joke and then i'm an idiot Link to post Share on other sites More sharing options...
sergiolov Posted August 30, 2007 Share #11 Posted August 30, 2007 Normal aliasing, stronger with lenses which maintain high contrast and resolution at the sensor's Nyquist frequency, around 54 line pairs mm with the m8. A pattern of fine lines creates this particular effect, that is masked by the use of the anti aliasing filter on other cameras. The following test shot illustrates the effect of line patterns with changing inclinations. Sergio. 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/32287-m8-moiree-kills-pictures/?do=findComment&comment=342554'>More sharing options...
gravastar Posted August 30, 2007 Share #12 Posted August 30, 2007 Here's another example taken with a Canon 1DsMkII. The buildings are in Sydney Harbour and have venetian blinds on the windows. You can see both moire and mosaic problems. I don't think there's anything wrong with davichan's M8 other than standard moire Bob. 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/32287-m8-moiree-kills-pictures/?do=findComment&comment=342560'>More sharing options...
Guest Walt Posted August 30, 2007 Share #13 Posted August 30, 2007 I have seen this occassionally on several bodies, including the "geometric" patterns. This has *always* been with venetian blinds (slat blinds) or other fine, repetitive detail behind glass. I think this is just another of the M8's special features. Walt Link to post Share on other sites More sharing options...
sean_reid Posted August 30, 2007 Share #14 Posted August 30, 2007 I find it very simple to correct using the C1 Moire plug-in for Photoshop. This is the trade-off for the superb resolution we get with no AA filter. My own preference would be for all of my cameras to have no AA filter. It's a small consolation, but moire like that is evidence that your lens provides a lot of resolution. Cheers, Sean Link to post Share on other sites More sharing options...
fursan Posted August 30, 2007 Share #15 Posted August 30, 2007 snip . . I think this is just another of the M8's special features. Walt how many special features are there in store for us? Link to post Share on other sites More sharing options...
Jamie Roberts Posted August 31, 2007 Share #16 Posted August 31, 2007 how many special features are there in store for us? Well, I guess as many as there are on a 1dsMark2.... Wow Bob... thanks for showing that. I've taken my share of venetian blind pix too, but well, wow! And it has an anti-alias filter. BTW--I get moire all the time with the 5D and the better Canon glass too. So there you go. Bridesmaid's dresses these days are made of some super shiny tightly woven stuff that just busts most sensors. Link to post Share on other sites More sharing options...
Makaveli45 Posted August 31, 2007 Share #17 Posted August 31, 2007 David, check your private messages please. thanks. Link to post Share on other sites More sharing options...
sean_reid Posted August 31, 2007 Share #18 Posted August 31, 2007 how many special features are there in store for us? Walt likes to joke about the M8 but moire is to be expected in any camera with no AA filter (as I explained in my review). It's not hard to correct. Link to post Share on other sites More sharing options...
gravastar Posted August 31, 2007 Share #19 Posted August 31, 2007 Well, I guess as many as there are on a 1dsMark2.... Wow Bob... thanks for showing that. I've taken my share of venetian blind pix too, but well, wow! And it has an anti-alias filter. BTW--I get moire all the time with the 5D and the better Canon glass too. So there you go. Bridesmaid's dresses these days are made of some super shiny tightly woven stuff that just busts most sensors. I thought I'd show that one to give a balanced perspective on the problem - that it's not specific to the M8. Interestingly what I have noticed with the 1Ds series is when the fine detail in the image is a harmonic (ie. higher frequency) than the pixel spacing the colored bands can be quite strong but there isn't much banding in the luminance channel. Bob. Link to post Share on other sites More sharing options...
wattsy Posted August 31, 2007 Share #20 Posted August 31, 2007 Walt likes to joke about the M8 but moire is to be expected in any camera with no AA filter (as I explained in my review). It's not hard to correct. I'm not sure why every issue with the M8 discussed here has to be given the full Panglossian spin. I think most people accept that the 'rainbow' colour moire effects are an unavoidable byproduct of sharp lenses, mild/missing AA filters, and fine frequency detail. What is new to me (though Bob has demonstrated it also happens with his Canon) is the addition of the maze-like geometric pattern effect. Unlike straightforward colour moire, I find the maze patterning effect less easy to remove (the effect is visible in both luminance and colour channels). Ideally I would like to be able to deal with the issue at the RAW conversion stage without globally softening (or otherwise reducing the detail of) an image. I'm most familiar with C1 - do any of the other RAW converters make it easier to reduce these geometric artefacts without reducing the detail on a global basis? Link to post Share on other sites More sharing options...
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