dchalfon Posted November 25, 2011 Share #1 Posted November 25, 2011 Advertisement (gone after registration) since having some IQ problems with my Leica M8 DNGs in Aperture 3 i've been trying C1 and the Camera Raw Developer that's embedded in Photoshop. I've just happened to save the files on Camera Raw as DNGs again and to my surprise they are half the size of the ones straight out of the camera (no i've had not reduced or cropped anything, simply saved them). and more, now when importing back to aperture it recognizes the lens... strange? to my eye the quality of the file seem to be same. should i add this step of saveing them o camera raw before going to aperture? Link to post Share on other sites More sharing options...
Advertisement Posted November 25, 2011 Posted November 25, 2011 Hi dchalfon, Take a look here smaller DNGs!. I'm sure you'll find what you were looking for!
pico Posted November 25, 2011 Share #2 Posted November 25, 2011 The behavior is similar in CS 5.5. The saved DNG is just less than half the size of Leica's DNG. I won't save as such again because disc space is cheap. I've no answer regarding quality. . Link to post Share on other sites More sharing options...
dchalfon Posted November 25, 2011 Author Share #3 Posted November 25, 2011 actually i started to explore options because of IQ. see my other post: http://www.l-camera-forum.com/leica-forum/digital-post-processing-forum/210619-captureone-aperture-workflow-anyone.html Link to post Share on other sites More sharing options...
hoppyman Posted November 26, 2011 Share #4 Posted November 26, 2011 Camera Raw (and the same engine in Lightroom) applies LOSSLESS compression to the DNG files automatically on import. Link to post Share on other sites More sharing options...
01af Posted November 26, 2011 Share #5 Posted November 26, 2011 I've just happened to save the files on Camera Raw as DNG files again and to my surprise they are half the size of the ones straight out of the camera ... Loading and saving DNG files through Camera Raw does the same to them as Adobe DNG Converter would do—it converts the DNG files to DNG format. While this may seem redundant and entirely pointless, it isn't. It will convert the files from DNG 1.0 format (which is what the digital Leica camera are using) to the current DNG 1.3 format which, among other things, includes a lossless compression. So the files are smaller but don't lose any quality. ... and more, now when importing back to Aperture it recognizes the lens. Upon reading a DNG file, Adobe Camera Raw, Adobe Bridge, and Adobe DNG Converter will also read the Lens ID from the Leica Maker Notes section in the file's EXIF data and translate them into regular EXIF and XMP metadata that Aperture can understand. This is a little extra service the Adobe products silently provide in the background ... not only for Leica files but for many brands' lens codes in their respective Maker Notes sections. However as of now, this does not work for a few lenses which include the Apo-Telyt-M 135 mm and the Super-Elmar-M 21 mm Asph because the Adobe products don't understand the most recent Leica lens codes yet. Link to post Share on other sites More sharing options...
hoppyman Posted November 26, 2011 Share #6 Posted November 26, 2011 That last is very useful additional information. There is another thread currently where the focal length but not the name is reported for an owner of the Super Elmar 21mm. Link to post Share on other sites More sharing options...
CheshireCat Posted April 29, 2012 Share #7 Posted April 29, 2012 Advertisement (gone after registration) Is there a way to apply this conversion to files that have already been imported in Lightroom ? Link to post Share on other sites More sharing options...
CheshireCat Posted May 1, 2012 Share #8 Posted May 1, 2012 Is there a way to apply this conversion to files that have already been imported in Lightroom ? Found the answer to my own question: select your photos in the Library and then "Metadata"->"Update DNG Preview & Metadata". Lightroom seems to apply lossless compression automatically when re-writing DNG files, and this makes a lot of sense. Well, actually it is the M9 not writing compressed files which does not make any sense... Link to post Share on other sites More sharing options...
mjh Posted May 1, 2012 Share #9 Posted May 1, 2012 Well, actually it is the M9 not writing compressed files which does not make any sense... The M9 does write compressed files if that’s what you tell it to do, it is just that this compression is lossy. The camera’s CPU cannot handle the computationally much more demanding task of lossless compression. Link to post Share on other sites More sharing options...
Jamie Roberts Posted May 1, 2012 Share #10 Posted May 1, 2012 I'm not sure what happens when you losslessly compress DNGs in LR. Can you still open them with C1, for example, or are you stuck with LR from them on ? Be aware, too, that if I recall the details correctly, LR 4 now also offers an additional "lossy" DNG compression. Unlike Leica's compression scheme, Adobe's applies JPEG compression to a demosaiced file, essentially "cooking" part of LR's take on the RAW file without losing the ability, in LR, to change white balance, etc... I know lots of people who are looking at this for their D800 files It's explained here: Adobe Photoshop Lightroom 4.0 Public Beta Feature Preview However, once you do compress the DNG this way, I don't believe you're going to be opening those files in C1 or Raw Developer anytime soon; just in LR / ACR. So if you don't like what Lightroom does to your files to begin with I'd be careful, even for storage purposes. Hard disk space is still getting cheaper every day... Well, almost every day! Link to post Share on other sites More sharing options...
k-hawinkler Posted May 1, 2012 Share #11 Posted May 1, 2012 Jamie, Isn't there a similar issue with not using side car files? My understanding is in order to keep all options open one should use side car files so that the original RAW files, for example .NEF, don't get modified. How do I use side car files for the .DNG coming from my M9 either in LR4 or CS6? Link to post Share on other sites More sharing options...
CheshireCat Posted May 2, 2012 Share #12 Posted May 2, 2012 The M9 does write compressed files if that’s what you tell it to do, it is just that this compression is lossy. The camera’s CPU cannot handle the computationally much more demanding task of lossless compression. I don't know which CPU is in the M9, but my educated guess is that this is more a software issue than a hardware one. Lossless JPEG is a very simple algorithm, simpler than lossy JPEG. Lossless JPEG would also halve the time to write a DNG to the SD card. It is really a no-brainer. Link to post Share on other sites More sharing options...
CheshireCat Posted May 2, 2012 Share #13 Posted May 2, 2012 I'm not sure what happens when you losslessly compress DNGs in LR. Can you still open them with C1, for example, or are you stuck with LR from them on ? I don't own C1, so I cannot tell. Lossless DNG uses lossless JPEG, which is a well known standard. Any good application should be able to handle a lossless DNG. Reading around, it seems that most interop issues are caused by the new LR4 option "Embed Fast Load Data". I don't know any technical detail about this option, so I cannot provide more information on this. Be aware, too, that if I recall the details correctly, LR 4 now also offers an additional "lossy" DNG compression. It stays off here. The new lossy compression mode seems to be unsupported by most applications. Besides, I don't like lossy compressions [for my photos]. In any case, it seems LR only uses lossless compression when you "Update DNG Preview & Metadata". This makes sense because - as the action name implies - the main image data are not affected (only the preview and metadata are modified), so LR is basically rewriting the same image data in a most efficient way. [...] So if you don't like what Lightroom does to your files to begin with I'd be careful, even for storage purposes. Hard disk space is still getting cheaper every day... Well, almost every day! This is a wise advice Link to post Share on other sites More sharing options...
mjh Posted May 2, 2012 Share #14 Posted May 2, 2012 I don't know which CPU is in the M9, but my educated guess is that this is more a software issue than a hardware one. They’ve tried it, it was too slow, they’ve dropped it. That was back in the days of the M8 but the M9 isn’t that different from the M8 so lossless compression is still not an option. Of course newer designs such as the S2 have faster processors but that’s a different story. Link to post Share on other sites More sharing options...
mjh Posted May 2, 2012 Share #15 Posted May 2, 2012 Any good application should be able to handle a lossless DNG. “Should” doesn’t imply “does”. Some raw converters expect raw files from a specific camera to be in the specific format(s) the camera is known to use, and since the M9 will never write losslessly compressed DNGs, such files might be rejected. Link to post Share on other sites More sharing options...
Jamie Roberts Posted May 3, 2012 Share #16 Posted May 3, 2012 Jamie, Isn't there a similar issue with not using side car files? My understanding is in order to keep all options open one should use side car files so that the original RAW files, for example .NEF, don't get modified. How do I use side car files for the .DNG coming from my M9 either in LR4 or CS6? Yes, I think that's the way with LR... but I'm a casual LR user. I only let it touch my working copies of DNG files. I'm still a C1 user through and through, and they just keep making it better. Link to post Share on other sites More sharing options...
Jamie Roberts Posted May 3, 2012 Share #17 Posted May 3, 2012 {snipped} The new lossy compression mode seems to be unsupported by most applications. Besides, I don't like lossy compressions [for my photos]. In any case, it seems LR only uses lossless compression when you "Update DNG Preview & Metadata". This makes sense because - as the action name implies - the main image data are not affected (only the preview and metadata are modified), so LR is basically rewriting the same image data in a most efficient way. {snipped}) Actually, I believe what happens is that when you import your raw files into Lightroom and you check lossy compression, then Lightroom will automatically create a demosaiced & JPEGed DNG of your original raw file. Now, in Leica case, that original is already a DNG, but in Canon or Nikon's case it isn't. Adobe are selling this as an archive or space-saving option, but as I mentioned before it does kind of lock you into their interpretation of your raw data. That might not, of course, be a problem. You can also export or transform all your raw files to lossy compressed DNGs. So it's definitely changing the data, and not just the preview. Of course, if you still have your original raws you can always go back... Link to post Share on other sites More sharing options...
CheshireCat Posted May 6, 2012 Share #18 Posted May 6, 2012 They’ve tried it, it was too slow, they’ve dropped it. That was back in the days of the M8 but the M9 isn’t that different from the M8 so lossless compression is still not an option. Of course newer designs such as the S2 have faster processors but that’s a different story. Can you cite the source ? This is ridiculous. Link to post Share on other sites More sharing options...
Lightwrangler Posted May 6, 2012 Share #19 Posted May 6, 2012 Can you cite the source ? Dumbest internet expression ever. This is ridiculous. The M8/9 do indeed have a quite limited cpu. So, can you enlighten us how you would have accomplished a faster compression? Mike Link to post Share on other sites More sharing options...
CheshireCat Posted May 6, 2012 Share #20 Posted May 6, 2012 Dumbest internet expression ever. And this is exactly the problem here. The M8/9 do indeed have a quite limited cpu. So, can you enlighten us how you would have accomplished a faster compression? if you care to read one of my posts above, you will see I already have. I could be more technical, but I am convinced you do not have the technical knowledge, and especially not the willingness to understand. Link to post Share on other sites More sharing options...
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