11 Replies Latest reply: Jun 22, 2012 9:13 AM by Jim Wilde RSS

    Why can't LR see the DNG's?

    pat agonia Community Member

      I really am utterly confused by LR.3.6

       

      What I am doing is for every new set of images, say a wedding, I am setting up a new catalogue on the off board HD.

       

      I then import the images as DNG's & that's after first off loading them as the original Nikon RAW files (I don't trust either LR or myself to get it right) onto another HD.

       

      So, now I have 2x copies.

      One original non-PP RAW files

      One open in LR as DNG's which I then work upon.

       

      Now, a few days later, I plug in the HD into my PC and Lo! File name is off line or missing.

       

      This happens more often than not, so maybe 75% of my work flow is stymatised by having to work out what's happened or I have to start again on the PP.

       

      At this point, I am trying to both open the .lrcat file either from within LR / File /  Open Recent or directly from the file on the offboard HD.

       

      I can see the DNG's but LR seems unable to do so.

       

      Grrrrrrrrrrrrrrrrrr!

       

      What error am I making?

       

      Thanks

        • 1. Re: Why can't LR see the DNG's?
          Jim Wilde Community Member

          pat agonia wrote:

           

           

          Now, a few days later, I plug in the HD into my PC and Lo! File name is off line or missing.

           

          What OS? Windows or Mac?

           

          If Windows, when you plug in the HD, is the drive letter always the same? If not, that would explain the problem.

          • 2. Re: Why can't LR see the DNG's?
            pat agonia Community Member

            ?

            No idea.

            PC, ergo it's Windows.

             

            I've opened the DNG's in Bridge CS5 now, having given up with LR for the moment and none of the changes are apparent.

            Why is this?

            Is not the Adobe software seeing / reading it's own data?

            • 3. Re: Why can't LR see the DNG's?
              Jim Wilde Community Member

              pat agonia wrote:

               

               

              I've opened the DNG's in Bridge CS5 now, having given up with LR for the moment and none of the changes are apparent.

              Why is this?

              Is not the Adobe software seeing / reading it's own data?

               

              Because Lightroom is a non-destructive editor, which means that changes you make within Lightroom are only stored in the catalog, the image file is not over-written. You can, however, have the edit information stored as XMP data in the header of the image file, which could then be read and interpreted by other Adobe software. But for Lightroom to be able to write that metadata back to the file, it has to be online.....so you're back with the original Lightroom problem of your files being missing.

               

              I ask again: when you plug in the HD is the drive letter always the same?

              • 4. Re: Why can't LR see the DNG's?
                dj_paige Community Member

                The default operation of Lightroom does not store metadata in DNG files. By default, Lightroom only stores metadata (including edits) in its catalog. So, in the default operation of Lightroom, the only place you can see the edits is to view the photos in Lightroom.

                 

                I suggest you look further into this issue of external drives changing letters, instead of saying "No idea". In particular, Lightroom will tell you the location (including drive letter) that it thinks the photos are located in. This can be seen in the Metadata Panel on the right of the Library Module. Then go to Windows and determine where the photos are actually located (including drive letter). If the drive letter or other part of the location and file name don't match, then there's your problem. If it is the drive letter, this is easy to fix. If there are some other parts of the filename/path that have changed, we can probably help you fix those issues as well.

                • 5. Re: Why can't LR see the DNG's?
                  pat agonia Community Member

                  How would I know?

                  Is there any way of knowing this? (above post may seem to have the answer, posted up whilst I was typing).

                   

                  I have several drives and I am using two USB ports.

                  If HDD X is the one with the images I require on it, how do I know which USB port it needs to go ito and in which order along side other drives and other ports?

                   

                  I assume that if I plug in HDD Y into port A then HDD X into port B then the drives become different drives to that were I to plug them into the same ports but in a different order ( HDD X into port B then HDD Y into port A) ?

                   

                  Compound this still further by swapping the two drives around and again in two different orders and you have 4 possible combinations I assume?

                   

                  Does the Mac suffer from this continual drive re-designation issue?

                  • 6. Re: Why can't LR see the DNG's?
                    pat agonia Community Member

                    I'm looking at the Library / Meta Data and no where does it say what drive the images are supposed to be in.

                    What are you seeing that I am am not?

                     

                    Thanks

                    • 7. Re: Why can't LR see the DNG's?
                      ssprengel CommunityMVP

                      Lightroom stores the full path to each image in the catalog including the drive letter, so the drive letter needs to remain the same as when you imported the files. 

                       

                      The drive letter does not necessarily change when you connect to a different USB port. Each drive has a unique signature so Windows is usually able to assign the same drive letter.  If you have multiple drives that all share the same drive letter, though, then this will be a problem if you have more than one plugged in at the same time, where Windows will necessarily have to assign a new drive letter to at least one of them.   If you also have drive-letters assigned to network locations, the local drive letters can be hidden by the network drive connections.

                       

                      Assuming you are on Windows 7, you can use Administrator Tools / Computer Management / Disk Manager / right-click-on-hard-drive / Change Drive Letter and Paths… to assign a different drive letter to each of your external drives so there won’t be conflicts if you plug in more than one at a time or to move the drive letters out from under any drive letters used for network locations  Once you have a different and consistent drive-letter for each drive then you can right-click on a wayward folder in Lightroom and choose Update Folder Location then navigate to the folder on whichever hard-drive the photos are on.

                      • 8. Re: Why can't LR see the DNG's?
                        pat agonia Community Member

                        Thanks.

                        I think I start to understand this. Maybe.

                        Is this normal?

                        That every user in the PC enviroment has to do this whole "Administrator Tools / Computer Management / Disk Manager / right-click-on-hard-drive / Change Drive Letter and Paths" business for every hard drive?

                         

                        Is changing the HD drive letter through this rather Windows procedure bizarre procedure going to help if I can't assess where the LR thinks it's info / image is actually stored  as I may simply send it a drive it's not looking for anyhow?

                         

                        How do I keep track of what each drive is called?

                        How do I copy / paste the LR catalogue and images to another HD as a back up and ever hope to see them again on that other HD if it has a different drive designation?

                         

                        Sorry - I do not know what you mean by the "network drive connectors" but since it's just me and two PC's and some HDD's I assume it's not a problem for me to consider?

                         

                        Thanks

                        • 9. Re: Why can't LR see the DNG's?
                          ssprengel CommunityMVP

                          Lightroom looks for the image where ever it was first imported from.  If the location is stable then there shouldn’t be any problem, although sometimes the upper-case/lower-case of the drive letter can be different and confuse Lightroom.

                           

                          You can see the drive letter in My Computer or Computer and usually in the title or address bar in Windows Explorer, and usually in the title of the AutoPlay window that pops up when you plug in a hard drive.

                           

                          You don’t copy/paste the images to another hard-drive to make LR see them, again.  You right-click on a folder in LR and choose Update Folder Location… and click over to where that folder is, now, whatever drive letter it is on.  LR will update the references to all the photos that are under that folder to the new location.  Do this “locating” after you’ve assigned consistent drive letters to each hard-drive.

                           

                          Is your problem that you are moving the hard-drive between two different PCs and the drive letter is different between the two PCs?  If so, then you will certainly want to assign the same drive letter to that hard-drive on both PCs and do the same thing for each hard-drive you connect to each PC.

                          • 10. Re: Why can't LR see the DNG's?
                            pat agonia Community Member

                            Hi.

                            OK. I worked out that the Explorer info gave me where it thought LR should be looking.

                            That was a start.

                            This is torturous!

                            Is this the same for Mac's as well?

                             

                            So, as I move my HD's about between PC's I have to re-assign drive letters and keep them thus the same between PC's?

                             

                            Will this assigning a drive letter going to be read by each of the 2x PC's and remain in tact between the two?

                            So if I give the drive a new drive letter, T, it will be thus on both PC's or will the two PC's try and give it a sequential drive letter depending on what else is plugged in?

                             

                            My head hurts.

                            • 11. Re: Why can't LR see the DNG's?
                              Jim Wilde Community Member

                              Unless you intervene, Windows will allocate the next available drive letter when you plug in an external drive. If you are in the habit of moving the external drive between different PCs, then it logically follows that there is a risk that the second PC will allocate a different drive letter (i.e. it depends on what the next available letter is on the second PC). Furthermore, when you reconnect the drive back to the original PC, it again may get a different drive letter than the last time if you have connected other devices in the interim.

                               

                              The very simple solution, which you only ever have to do once, is to allocate a specific drive letter (and a drive name helps as well), and choose one near the end of the alphabet (so it won't get affected by other device connections), e.g. drive X. Then do exactly the same on the second PC. Ideally you would have done this before starting to import files into Lightroom, but as you haven't you'll need to do the "Update Folder Location" process as outlined, and the problem should be sorted