16 Replies Latest reply on Oct 20, 2014 6:17 PM by areohbee

    Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?

    PenaltyShot Level 1

      This is a stupid question that somehow, after hours of searching, I can't find a definitive answer for:

       

      I have an existing catalog of photos that are stored in .CR2 (Canon RAW) format, plus accompanying XMP sidecar files on the photos I've edited.  If I decide to convert those to DNG, does the conversion process automatically pick up the edits I've done from the XMP files and write those edits into the resulting DNG?  Or does the conversion process just convert the CR2 --> DNG only, ignoring the XMP sidecar file?

       

      Stupid question, but a really important one!

       

      Bonus question:

      Does the conversion process leave the CR2 and XMP files in the folder as they are, and just add the DNG in addition to those?  Or does it delete the source CR2 and XMP files, REPLACING those with the DNG?

        • 1. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
          areohbee Level 5

          The conversion (when done by Lightroom) picks up the edits you've done from the catalog, not the xmp sidecars (in case there is a difference - in best world, there won't be). You can always store those edits in xmp embedded in the DNG after conversion by using 'Save Metadata..' function of Library/Metadata menu.

           

          PS - If conversion done by Adobe DNG Converter, then edits will be picked up from the xmp sidecars, and stored in xmp embedded in the DNG (so when you import in Lightroom, edits are present).

           

          Rob

          • 2. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
            ssprengel Adobe Community Professional & MVP

            The DNGC should pick up what is in the XMP but one of the last versions, maybe 8.6 or maybe 8.5, ignored the XMP and would always convert with Adobe Defaults.  I was supposedly fixed, in the next version, but if the current version is bad, then the “next version” would be the beta DNGC 8.7 RC from Adobe Labs – CS6 branch of the ACR 8.7 RC links:

             

            http://labs.adobe.com/

            • 3. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
              PenaltyShot Level 1

              Thanks, guys. 

              I hadn't realized that editing changes were stored in the catalog as well as in the sidecars.  I thought that if the sidecars were somehow lost or got corrupted, the edits would be lost.  So, that's good to know that the catalog stores this stuff also.

              I have been going back and forth on converting / not converting, but I think I am going to go for it.  It just seems like I have nothing really to use, as long as I am in the Adobe ecosystem and using Lightroom (and third-party plugins).  Smaller file size, only one file for the original photo + edits, an arguably more universal format than Canon's CR2 RAW, and no loss in image quality.  I think I'll convert to DNG, then after I am absolutely certain that all converted correctly and that the DNG is functionally identical to my original RAWs + edits, I'll delete the CR2 and XMP files.

              • 4. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                dj_paige Level 9

                I hadn't realized that editing changes were stored in the catalog as well as in the sidecars

                By default, the edits are ONLY stored in the catalog file and not in the sidecars. If you want the edits to be stored in the sidecar file, you have to turn on an option or use Ctrl/Cmd-S. So if the sidecars somehow got lost, you don't lose your edits.

                • 5. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                  PenaltyShot Level 1

                  So what do the sidecar files store by default, anyway?  I thought their whole purpose was to store Develop settings.

                  • 6. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                    dj_paige Level 9

                    The default mode of Lightroom does not create sidecar files. There are none.

                     

                    Even when sidecar files are present, Lightroom does not use them for anything, Lightroom uses the information in the catalog file (except when importing, in that case the develop settings in the sidecar files are written into Lightroom's database and then used to display the photo)

                     

                    The purpose of sidecar files for other software is indeed to store develop settings, as there was no other place to put this information; however this is not the purpose of sidecar files in Lightroom. When present, the sidecar files are simply a way to store your develop settings outside of Lightroom and allows Lightroom adjustments to be communicated to other software that can read Lightroom develop settings.

                    • 7. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                      PenaltyShot Level 1

                      Ahhh...OK, that makes perfect sense.

                       

                      I think I'll press onward with my plan to convert my catalog to DNG (then eventually use those as the master negatives, and delete the CR2 + sidecars).

                       

                      Thanks for your help!

                       

                      Mark

                      • 8. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                        areohbee Level 5

                        PenaltyShot wrote:

                         

                        ..delete the CR2..

                        Adobe-converted DNGs can sometimes not be opened in non-Adobe software (even apps which tout support for DNG format). Make sure you don't mind committing to use Adobe/compatible software forever before you delete your CR2's.

                         

                        To be clear: Adobe makes sure all their software can read their converted DNGs, whereas in other vendor's (DNG-supporting) software it's more hit n' miss: maybe they can open one flavor, but not another etc. And of course some software just doesn't read DNGs at all, like Canon's DPP.

                        • 9. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                          PenaltyShot Level 1

                          Have you run into any really important / crucial ones to your workflow that don't support DNG?

                          I find that I do my basic developing in Lightroom itself, and a lot of times that's enough.  But I also have the Nik Complete Collection (Color Efex, Silver Efex, HDR Efex, etc.), Portrait Professional, Photomatix, DxO Viewpoint, and a couple other ones that I use when needed.  With those, I "edit a copy with Lightroom adjustments" and it makes a TIFF file (or sometimes I make a PSD), and the plugin edits that file anyway rather than editing the DNG directly.

                           

                          Of course, things change, and maybe I'll run into some tool in the future that doesn't take DNG files.  On the other hand, it seems like the CR2 format could be orphaned just as easily, in the future.  I know the pros/cons of "to DNG or not to DNG" have been discussed ad nauseum, so I won't get into all that here.  Still, maybe making some archival backup of my CR2 + sidecar files somewhere before deleting them from my main storage device would be a good idea.

                          • 10. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                            areohbee Level 5

                            PenaltyShot wrote:

                             

                            Have you run into any really important / crucial ones to your workflow that don't support DNG?

                            really important / crucial?, to me? - never.

                             

                            Don't get me wrong: some people *love* the feeling they get when deleting the original proprietary raws - like they're standing up for a cause or something. If you are such a person, then by all means: knock yourself out, and enjoy - nothing terrible is likely to happen (unless Adobe goes under and/or DNG format falls flat..).

                             

                            I have discovered a surprisingly large number of cases where some (Adobe-converted) DNGs were not readable, e.g.

                            * Bibble

                            * CaptureOne

                            * DxO

                             

                            (note: original proprietary raws were fine).

                             

                            All of which purport support for DNG (and likely read out-of-camera DNGs from supported models just fine).

                             

                            And if you search the forums you can discover more..

                             

                            (in case Adobe responds (rare): "it's not our fault - programmers must not have read the spec closely enough..". On the other hand, Adobe is sometimes a year or so tardy when it comes to releasing the new spec - hmm.. - I guess turn-about is fair play (Nikon is sometimes tardy with NEF documentation which supports new cameras, forcing Adobe to work without (reverse-engineer) for the mean time..).

                             

                            Two other software's that don't support DNG:

                            * Canon's DPP (and other Canon software).

                            * Nikon's NX2 (and other Nikon software).

                             

                            If you want to display focus points, proprietary raw is required, period.

                             

                            Me? If I were to bother to convert raw files to DNG, I would do the opposite of what most people do - instead of archiving the originals and using the DNGs, I'd archive the DNGs and use the originals. That way, I can open my photos in any software I choose, and/or see focus points if I feel like it, but if I get cryogenically frozen for a few decades whilst DNG wins the format war, I'll have the DNGs to use.

                             

                            To each their own, just realize: DNG is not a standard, yet, and may never be, so you are playing the odds (burning bridges) if you discard originals. Adobe really wants it to be a standard, because it gives them an edge over their competitors (since Adobe controls the spec, and when it's released..), so if you want to help ensure Adobe success in the format war, then by all means: delete your originals.

                             

                            To be clear: I personally support the DNG format, completely. I just don't convert my existing raws to DNG yet, and generally recommend to others who convert: keep your originals.

                             

                            Rob

                            • 11. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                              PenaltyShot Level 1

                              You make some good points, and no, I'm definitely not the type that is doing this "for a cause" or something like that.  I just thought that DNG sounded like it had some attractive points, and liked the idea of not having sidecar files.  DNGs seem cleaner to me in that respect.

                               

                              Your reverse method of using DNGs as your archives and keeping the RAW originals as the negatives that you work with is an interesting one.  I might just do that.

                               

                              Lots of pros and cons -- not sure now what I'll do.  But thanks for the input; it forced me to rethink this a bit.

                              • 12. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                                DdeGannes Adobe Community Professional

                                Quote "and liked the idea of not having sidecar files.  DNGs seem cleaner to me in that respect."

                                If you think through the process, using Lightroom  you do not need XMP files or DNG files.

                                 

                                My main reason for adopting Lightroom as my main processor for RAW files is the fact that every thing I do is stored in the Catalog file and maintaining proper backups is all that I need to do for my work to be secure. No xmp or dng, I just keep it simple sweet.

                                 

                                I still consider raw processing software to be in a phase of rapid development, and keeping copies of my raw data with the best options for processing in the future with all options and applications a priority. Adobe may not necessarily be the best option in the future.

                                • 13. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                                  dj_paige Level 9

                                    I just thought that DNG sounded like it had some attractive points, and liked the idea of not having sidecar files.  DNGs seem cleaner to me in that respect.

                                  If you use Lightroom for all of your photo management (and I mean ALL), which I think you should do if you commit to Lightroom, then you never see the XMP files (even if you have Lightroom create the XMP files). The only time you would see XMP files is if you insist on managing your photos in your operating system (which I don't think you should do if you commit to Lightroom). So for me, the presence of XMP files is a complete non-issue. It's "cleaner" to me because I don't have the extra step of converting to DNG.

                                   

                                  Not using DNG is also superior to me in the sense that if I make a change and write the changes to XMP (which I do automatically), my backup program only has to make a backup of a 10-20 KB XMP file, but if I had DNG files, I'd have to make a backup of an approximately 15MB DNG file.

                                  • 14. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                                    john beardsworth Adobe Community Professional & MVP

                                    dj_paige wrote:

                                     

                                    Not using DNG is also superior to me in the sense that if I make a change and write the changes to XMP (which I do automatically), my backup program only has to make a backup of a 10-20 KB XMP file, but if I had DNG files, I'd have to make a backup of an approximately 15MB DNG file.

                                     

                                    No - adopting a DNG workflow means fine tuning your backup strategy. DNGs only need backing up a single time when they are created, not continually. Once you have these "virgin" backup copies, it doesn't matter if Lightroom saves metadata to its "working" copies of the DNGs. You backup your adjustment and other work by doing a routine backup of your Lightroom catalogue, and this contains 100% of what you've done to these images (which xmp doesn't).

                                    • 16. Re: Does converting RAW CR2 + XMP convert both of those into the DNG file, or does it just convert the CR2?
                                      areohbee Level 5

                                      PenaltyShot wrote:

                                       

                                      I finally decided to just forget about DNG altogether.

                                      That may very-well be the simplest solution, and unless you really need the things DNG offers (or vice versa), file format is pretty-much-of-a "don't care" (doesn't matter), as long as your software reads your files I mean.

                                       

                                      Note: if you want to revert existing DNGs back to original format, consider the UnDNG plugin (free, by me).

                                       

                                      Note2: if DNG lives, and so do you, then you can always convert in the future if you change your mind (unless of course you are cryogenically frozen for so long that the conversion tools no longer exist ).

                                       

                                      Cheers,

                                      Rob