7 Replies Latest reply on Sep 24, 2009 1:42 PM by b_gossweiler

    Q: save DNG only or DNG + Original RAW?

    harryshin Level 1

      Hi:

       

      1.  I realize that this has been asked before, but... it's never been definitively answered  (at least to my satisfaction) and thus hopefully someone will be able to clarify this issue for me.

       

      2.  I currently convert all of my "important" RAW files to DNG (ie perhaps 10-20% of total RAW files) and keep the original RAW files along with the converted DNG files.  I do this just because I'm paranoid and probably because I haven't logically thought this process through.    But with increasing file sizes, I'm wondering what the "best" workflow would be:  A)  Covert all RAW files--> DNG and just keep those  B)  Convert all RAW files to DNG and keep everything  C)  Convert only the important RAW files to DNG and keep RAW + DNG (ie my current workflow)  D)  Convert all RAW files to DNG and keep the DNGs but only the important original RAW files. 

       

      3.  At the core of the issue (at least for me) is whether there is any pragmatic difference between the original RAW file vs DNG.   Obviously, there is a difference otherwise, there would not be two products.   I'm just unclear as to whether the proprietary "stuff" inside a RAW file is of any importance down the road.

       

       

      Thanks for any helpful information.  Harry Shin

        • 1. Re: Q: save DNG only or DNG + Original RAW?
          xbytor2 Level 4

          Making things simple is always a good idea and your current approach is fine.

          1) Keep all raw files. They are your negatives. Archive them and keep them safe.

          2) Convert the 'important' ones to DNG and work on the DNG files. Make backups as needed.

           

          On the rare occasion that you absolutely have to have the original raw file, get it from your archive.

          I haven't had the need to resort to my raw files for any of my work, but my demands aren't that

          severe. You needs may be different.

           

          Also, I use metadata heavily to manage my workflows. DNG's direct XMP support makes life much easier for me.

          • 2. Re: Q: save DNG only or DNG + Original RAW?
            b_gossweiler Level 5

            One more option would be to convert the RAW files to DNG and embed the original RAW file in the DNG. This always leaves you - as long as you have a working copy of Adobe DNG Converter available - with the ability to extract the original RAW files at any time again.

             

            Advantage: You don't have to manage so many different files for backup etc.

            Disadvantage: Loosing the DNG means loosing everything, larger DNG file size

             

            Beat Gossweiler

            Switzerland

            • 3. Re: Q: save DNG only or DNG + Original RAW?
              JimHess-5IFZWq Level 3

              I am curious to understand why some of you feel it is necessary to create a DNG copy of the raw image to work on.  Do you feel that you are protecting your raw image data somehow?  Surely you understand that neither Camera Raw nor Lightroom alter the raw image data in any way.  All changes are metadata changes only.  So what is the advantage of working on a DNG file rather than the original raw file?  Not trying to start an argument, just trying to understand.

              • 4. Re: Q: save DNG only or DNG + Original RAW?
                JimGoshorn Level 2

                For me it is three fold:

                 

                1. It is an open format

                2. It saves space on the drive

                3. The metadata is embedded in the DNG file so everything is in one place

                 

                Jim

                • 5. Re: Q: save DNG only or DNG + Original RAW?
                  JimHess-5IFZWq Level 3

                  JimGoshorn wrote:

                   

                  For me it is three fold:

                   

                  1. It is an open format

                   

                  2. It saves space on the drive

                  3. The metadata is embedded in the DNG file so everything is in one place

                   

                  Jim

                  1.  Yes, that is true as far as Adobe is concerned.  However, in most cases, if you ever want to use the software provided by the camera manufacturer, that software cannot read the DNG files.  And while a lot more of the third-party software vendors are beginning to support DNG, there are still quite a few that don't.  So it's not as "open" as it might seem.

                   

                  2.  Does it really save space?  If you keep your original raw file as a backup along with the DNG it doesn't save space, but rather uses more.  And that savings varies.  The files from one of my cameras are 50% smaller.  But the files from the camera I use the most are only about 15% smaller.

                   

                  3.  That is one of the main reasons I used DNG files for a while.  But what puzzles me is when I read comments from some users who are frustrated because they don't have XMP files with their DNG files.  Now that I use Lightroom for most of my raw editing I don't have to worry about XMP files anyway.  I use Lightroom in its default setup where all of the changes are stored within the database.

                   

                  So I am kind of torn as to the real advantage of using DNG files.  I know all of your arguments and have considered them.  The Adobe experts are quite favorable toward using DNG.  But my workflow doesn't seem to benefit greatly from converting, although I do it occasionally.  I'm not saying that your arguments are wrong, nor am I implying that mine are right.  I'm just not sure I see a real benefit as far as I'm concerned.

                  • 6. Re: Q: save DNG only or DNG + Original RAW?
                    xbytor2 Level 4
                    [1. It is an open format]

                    1.  And while a lot more of the third-party software vendors are beginning to support DNG, there are still quite a few that don't.  So it's not as "open" as it might seem.

                    "Widely supported" and "open" do not necessarily go hand in hand. But wide support for DNG does seem somewhat inevitable. The fact that it is open (though not quite as complete and polished as it could be) does make it possible to have wide-spread 3rd party support.

                     

                    [2. It saves space on the drive]

                    This size of image files can be smaller after conversion to DNG but usually not. And typically the difference is not important either way. However, since you need keep or embed the raw files, you're going to take a diskspace hit regardless.

                     

                    [3. The metadata is embedded in the DNG file so everything is in one place]

                    3.  That is one of the main reasons I used DNG files for a while.  But what puzzles me is when I read comments from some users who are frustrated because they don't have XMP files with their DNG files.

                    You can have sidecar XMP files and you can extract the XMP data to a file (via exiftool). But having the metadata in the file just makes life a lot easier. If you are using tools like Lr or an asset management system, this is less of an issue.

                    • 7. Re: Q: save DNG only or DNG + Original RAW?
                      b_gossweiler Level 5

                      I basically agree with JimHess. Thousands of lines have been written on that subject, e.g. in To DNG or Not to DNG... That is the question or in Long term viability of DNG and many many more.

                       

                      I think Jao vdL brought it to the point in his post here (within Thread Long term viability of DNG).

                       

                      For me (I work with CR2 and not DNG in my workflow) the most important advantage of using DNG would be to keep the XMP data within the file itself and not as sidecar file.

                       

                      One argument concerning JimGoshorn's point 1:

                      DNG is not an open format, it is a documented, but still proprietary format of Adobe.

                       

                      I for myself don't convert my CR2 to DNG now. I think if - at some point of time in the future - support for my CR2 files in software (like LR) will run out, I still have the option of converting all of them as a batch with the last supporting version at that point of time.

                       

                      Beat Gossweiler

                      Switzerland