theboch Posted September 26, 2012 Share #21 Posted September 26, 2012 Advertisement (gone after registration) Is there software that can compare the data written to two or more cards, after transfer to the computer, to see if that data is the same? That way one could narrow down the problem to a specific camera, card, or card reader. Calculate CRC32 checksums with cksum - Mac OS X Hints Link to post Share on other sites More sharing options...
Advertisement Posted September 26, 2012 Posted September 26, 2012 Hi theboch, Take a look here M9 Banding and noise issues are gone!. I'm sure you'll find what you were looking for!
Paul J Posted September 26, 2012 Author Share #22 Posted September 26, 2012 (fps) etc. Hmmm...you just reminded me. The problem was worse on a series of shots either in C mode or a series in normal mode. The banding would get progressively worse in the series particularly when i had hit the buffer and it was writing whilst shooting. To me it tends to be power related and the card is clearly a determining factor. Link to post Share on other sites More sharing options...
theboch Posted September 26, 2012 Share #23 Posted September 26, 2012 Also, if the data transfer is the matter for the banding, this means the error in the data transfer occurs in a periodic manner. Otherwise the wrong data should more result in random artifacts and pixels/color information at the wrong position?! Link to post Share on other sites More sharing options...
theboch Posted September 26, 2012 Share #24 Posted September 26, 2012 Hmmm...you just reminded me. The problem was worse on a series of shots either in C mode or a series in normal mode. The banding would get progressively worse in the series particularly when i had hit the buffer and it was writing whilst shooting. To me it tends to be power related and the card is clearly a determining factor. I am sure Leica does not do a lot of checks if the data written to the SD card is valid. And the same as in the buffer... Normally they should check if the file is the same and if not send the data again. But maybe they did not implement such a feature because of power or CPU processing limitations. Link to post Share on other sites More sharing options...
Paul J Posted September 26, 2012 Author Share #25 Posted September 26, 2012 Oh...you mean like this? 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/188757-m9-banding-and-noise-issues-are-gone/?do=findComment&comment=2125604'>More sharing options...
Paul J Posted September 26, 2012 Author Share #26 Posted September 26, 2012 That one only turned up once. Go figure. All I know is my problems are GONE. I would have never thought cards could be so problematic. But I hear the same things with all systems. Just good to know that you can eliminate a concern in your life. I really thought I had a dud camera or it what some reported, as a feature of the M9. It's not true at all. If you have a problem try changing cards. Link to post Share on other sites More sharing options...
pico Posted September 26, 2012 Share #27 Posted September 26, 2012 Advertisement (gone after registration) How would this make sense? First, thank you Paul! Rick, most cards are susceptible to physical corruption. Stuff happens. Part of the card is a complex computer circuit that talks to the camera to confirm proper writes to the card. Some card manufacturers don't follow the standards to permit such checks, and some camera makers do not write their firmware code to use the check-codes, or they simply ignore errors. Such happens all the time in the computer biz. Link to post Share on other sites More sharing options...
jaques Posted September 26, 2012 Share #28 Posted September 26, 2012 it is weird- I use the cheapest cards that I get off the counter at my post office. I never have an issue with these cards... I only use 4 and 8 gig cards that cost 11$ or so... the only times I have had weird sensor/noise/banding issues has been when the battery is about to die... Link to post Share on other sites More sharing options...
Rick Posted September 26, 2012 Share #29 Posted September 26, 2012 Pico, I'm not sure that what we are seeing is a card problem. Banding noise is introduced by the camera when it reads data from the digital sensor. I'd be interested if the noise increases with ISO, for example. Link to post Share on other sites More sharing options...
wattsy Posted September 26, 2012 Share #30 Posted September 26, 2012 I don't think the body writes different to each different card. I think the cards record differently based on the quality of the card. I understand the distinction but I don't understand how the card influences the actual data (other than instances where it is obviously corrupted – bits missing, etc.). Doesn't the camera just feed the card a bunch of 0s and1s? If the camera recorded to analogue tape I could understand that the interface and/or tape mechanism might introduce additional noise but to a solid state memory card via a digital interface? Link to post Share on other sites More sharing options...
wattsy Posted September 26, 2012 Share #31 Posted September 26, 2012 Thinking about this more surely the banding noise has to be created upstream of the buffer – somewhere in the analogue to digital conversion. It seems a bit like voodoo blaming it on the card. Link to post Share on other sites More sharing options...
k-hawinkler Posted September 26, 2012 Share #32 Posted September 26, 2012 Thinking about this more surely the banding noise has to be created upstream of the buffer – somewhere in the analogue to digital conversion. It seems a bit like voodoo blaming it on the card. It would be interesting to see if the problem still persists with the latest firmware that supposedly has better power management, IIRC? Link to post Share on other sites More sharing options...
AlanG Posted September 26, 2012 Share #33 Posted September 26, 2012 Calculate CRC32 checksums with cksum - Mac OS X Hints Thanks. I figured there would be command line methods just as there have always been when copying files back in my CPM and DOS days. I guess this can compare the copied image on the computer's HD with the one on the SD card. So it would show if anything was changed in the transfer process. And maybe there are transfer programs that have a verify function. But I don't know how you could compare two different if "identical" images shot on two different cards. Perhaps a visual inspection is the only way. Link to post Share on other sites More sharing options...
pico Posted September 26, 2012 Share #34 Posted September 26, 2012 Doesn't the camera just feed the card a bunch of 0s and1s? At root everything is 0 or 1, but there are signaling protocols (commands) for the card that the camera is supposed to note, others that are optional, and others that are strongly recommended. It is a programming interface and not just a stream of bits stored in the card as if one were just pouring bits into a bucket. Link to post Share on other sites More sharing options...
Paul J Posted September 26, 2012 Author Share #35 Posted September 26, 2012 The problem has only disappeared with the change of card. I'm not saying it is the card that caused it but it is definitely related as I haven't seen the issue in a couple thousand shots now. It was in every other shot, or with one card in particular, it was in practically every shot. I'll will leave the diagnosis to the experts among us but the change of card has certainly rid me of my woes which is really all I'm concerned about. In answer to the question above, yes the banding and noise become heavier with the increase in ISO. Also regarding the firmware update, I understand the ability to tether is lost with 1.196. So I stayed at 1.176. Link to post Share on other sites More sharing options...
pico Posted September 26, 2012 Share #36 Posted September 26, 2012 Also regarding the firmware update, I understand the ability to tether is lost with 1.196. So I stayed at 1.176. Perhaps another mystery. My M9 does work tethered (to a Mac) with 1.196 Link to post Share on other sites More sharing options...
Paul J Posted September 26, 2012 Author Share #37 Posted September 26, 2012 Oh! Well that's interesting! THanks for letting me know. I don't know where I got that. I had read a couple of instances somewhere on the forum here I believe. Hmmm...even still. Now I have everything working as well as it is I'm going to stick with what I have and not move a muscle. Link to post Share on other sites More sharing options...
k-hawinkler Posted September 26, 2012 Share #38 Posted September 26, 2012 Paul, I am glad you found a combination of equipment that finally seems to work as it is supposed to and wish you continued good luck! Link to post Share on other sites More sharing options...
Rick Posted September 26, 2012 Share #39 Posted September 26, 2012 Thinking about this more surely the banding noise has to be created upstream of the buffer – somewhere in the analogue to digital conversion. It seems a bit like voodoo blaming it on the card. Maybe, we need to cover the cards with green marker, you know, like those green markers they used to try and sell us to use on the bottom of our CDs to make them sound better. p.s. Paul, just having fun, I believe you, I just don't understand why, either. Link to post Share on other sites More sharing options...
k-hawinkler Posted September 26, 2012 Share #40 Posted September 26, 2012 Perhaps another mystery. My M9 does work tethered (to a Mac) with 1.196 Hi Pico, Which software do you use for tethering? Thanks. Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.