10 Replies Latest reply on Jul 14, 2009 2:04 AM by ows-wales

    Preserving original DNG settings without Embedding RAW original

    ows-wales

      I'm hoping somebody can give me some guidance on the best workflow for editing DNG files after conversion from RAW format. Here is an outline of my problem:

       

      I shoot all my photos using .NEF RAW format. I then convert these files into DNG format using the Adobe converter. My main reason for doing this is to eliminate the use of sidecar files or using a central database to store RAW edits - I prefer the concept of 1 photo = 1 file. It also eliminates the possibility of forgetting to copy a sidecar file or the central database when moving files onto new pcs / hard disks etc.

       

      My question is how can you save your edited DNG files (exposure, white balance etc.) whilst retaining the original settings? I prefer not to embed the original RAW file as this will add to file size dramatically. What I would like to be able to do is open a DNG file, make some edits, save the file (by overwritting - not creating a new DNG file) and then be able to revert to the original DNG at a later date.

       

      Is this possible? How do most people work with DNG files as regards saving edits? Is it really a case of saving new DNG files after every edit?

       

      Hoping somebody can help!

       

      Cheers!

        • 1. Re: Preserving original DNG settings without Embedding RAW original
          Ramón G Castañeda Level 4

          ows-wales wrote:

           

          …to eliminate the use of sidecar files or using a central database…

           

          Just FYI, if you're talking about Bridge, you should note that the Central Cache is always on, even if you're set to "distributed folders".

           

          ows-wales wrote:


          My question is how can you save your edited DNG files (exposure, white balance etc.) whilst retaining the original settings? …

           

          Is this possible? …

           

          The raw image data in your DNG files, as in your raw NEF files, is never touched by Photoshop, ACR or Bridge.  As far as these three applications are concerned, raw files (including DNGs) are treated as read-only.

           

          Just run a quick test.  Do what you propose to do, then see how easy it is to undo your adjustments.

          • 2. Re: Preserving original DNG settings without Embedding RAW original
            xbytor2 Level 4
            Is this possible? How do most people work with DNG files as regards saving edits? Is it really a case of saving new DNG files after every edit?

             

            You can reset the settings (to Defaults) via ACR or Bridge. You can also save snapshots of your settings in ACR 5.4 and keep multiple states in the DNG file, but I don't have any practical experience with that feature. If I were really concerned about maintaing DNG edit histories, I would use exiftool to extract the XMP settings and use CVS (or subversion) for version control of that file, complete with tags, etc... That way I could roll back to settings at a particular date and time by checking them out of CVS and applying them to the DNG file with exiftool. I don't currently need that level of control, but if I were doing forensics work, for instance, I can see where that might come in handy.

             

            -X

            1 person found this helpful
            • 3. Re: Preserving original DNG settings without Embedding RAW original
              ows-wales Level 1

              Right, I'm beginning to get my head round this.

               

              If I use the snapshots settings in feature in ACR 5.4 (by the way, how do I access this?) does this mean that in Photoshop I can:

               

              1. Open a newly converted (from RAW) DNG file.

               

              2. Apply RAW edits - crops, colour etc.

               

              3. Update / Overwrite the DNG file using the snaphot feature.

               

              4. At a later date, open the DNG file in Photoshop or any other DNG-compatible software or even on another computer and see the original RAW version (as it came off the camera) as well as an edited version.

               

              Cheers!

              • 4. Re: Preserving original DNG settings without Embedding RAW original
                ows-wales Level 1

                Thanks for your reply.

                 

                However, I'm slightly confused when you say

                 

                'As far as these three applications are concerned, raw files (including DNGs) are treated as read-only'

                 

                I was under the impression that one big advantage of DNG files over RAW is that the RAW edits are saved as part of the file and not through the use of a centralised database or annoying sidecar files. Isn't the XMP data written to the header of a DNG file? Surely this means that DNG files are not 'read-only'.

                 

                Anyway, another user suggested that you can use snaphots of camera RAW settings within a DNG file - do you have any experience usaing this method?

                 

                All I want really is to have a dng file (not linked to any database or latched onto a sidecar file) on my computer that will open on any PC with compatible DNG software and have the original camera settings as well as edited RAW settings embedded in the file.

                 

                Cheers!

                • 5. Re: Preserving original DNG settings without Embedding RAW original
                  JimHess-hP0R75

                  Photoshop makes no changes whatsoever to the DNG file.  All changes or adjustments to the DNG are stored in the DNG, and any changes (including resetting the image to its original state) must be done within Camera Raw.  As soon as you have opened a DNG file into Photoshop and made additional adjustments, that image must be saved to a new file (JPEG, TIFF or PSD) because Photoshop cannot write changes to a DNG file or any raw file.  But using Camera Raw, it is always possible to restore a DNG file to its original state.

                  1 person found this helpful
                  • 6. Re: Preserving original DNG settings without Embedding RAW original
                    xbytor2 Level 4
                    I was under the impression that one big advantage of DNG files over RAW is that the RAW edits are saved as part of the file and not through the use of a centralised database or annoying sidecar files. Isn't the XMP data written to the header of a DNG file? Surely this means that DNG files are not 'read-only'.

                     

                    The image data in a DNG file is read-only. The metadata (XMP info) can be read and modified by any DNG/XMP compatible program. When you edit a DNG file with Camera Raw, it modifies the XMP info. However, most the interesting edits that you make with Camera Raw can only be rendered correctly with Camera Raw. Other DNG programs use different mechanisms for sharpening, for instance, so these XMP edits are Camera Raw specific.

                     

                    When I say 'Camera Raw' above I also mean 'Lightroom' as the two share a common raw processing code base.

                     

                    If I use the snapshots settings in feature in ACR 5.4 (by the way, how do I access this?) does this mean that in Photoshop I can:

                     

                    The Snapshots feature in CR is the far right icon button beneath the histogram panel.

                     

                    As long you don't actually open the image in PS and stay in ACR, your edits will be saved to the DNG file. Once the file is fully opened in PS, it cannot be saved back to DNG, as Jim says elsewhere.

                    • 7. Re: Preserving original DNG settings without Embedding RAW original
                      ows-wales Level 1

                      Ok, thank-you all for your help!

                      • 8. Re: Preserving original DNG settings without Embedding RAW original
                        ows-wales Level 1

                        Thanks for your help, I'll have a look at ACR tonight!

                        • 9. Re: Preserving original DNG settings without Embedding RAW original
                          Panoholic Level 2
                          My question is how can you save your edited DNG files (exposure, white balance etc.) whilst retaining the original settings?

                           

                          You can not retain the original settings, for there are none recognized. Following the NEF-to-DNG conversion you start out without any explicite settings, i.e. the default settings saved in ACR apply (if you did not save any setting yet as "default", then the "defaults of the defaults" apply). The settings you made in-camera are not taken over by the DNG converter (contrast, saturation, tone, sharpening, curve point modifications, etc.).

                           

                          There is one exception I know of (are there more?), namely the white balance; you can revert to the original setting by selecting As Shot.

                           

                          Gabor

                          • 10. Re: Preserving original DNG settings without Embedding RAW original
                            ows-wales Level 1

                            Tried out ACR last night with 100% success as regards my problem.

                             

                            It was so easy. All I needed to be able to do was to see DNG files within Bridge excactly as they came off the camera - or at least how they look like if I viewed them in camera. I then wanted to process them as regards white balance, exposure, cropping etc. and update the DNG file (by pressing DONE).

                            I then wanted to be able to revert my changes so that I can go back to the 'in camera' version.

                             

                            I'm not at home at the moment and therefore do not have access to my PC, but off the top of my head there was an option named something like RESET or Revert that worked perfectly. There is also a snapshot function available that works even better - I can now have several XMP 'profiles' to the same image (e.g a 5X4 crop in colour and a 4X6 B&W crop). All this with minimal increases in file size and without the need for annoying sidecar files or a centralised database.

                             

                            Unless I'm missing something (please point it out to me if I am!) then I have achieved 100% was I set out to achieve. Thank you everybody!