7 Replies Latest reply on Feb 3, 2010 12:08 AM by digitaloxygen

    Problem with Apple Core Image?

    Photo_op8 Level 1

      Can anyone confirm for me that there is an issue with Apple's Core Image as it relates to DNG. I am having problems with Nikon RAWs converted with DNG Converter. Once adjustments have been made to these DNGs (in Lightroom 2.3) and metadata and previews updated, software (Preview, etc.) relying on Core Image do NOT appear to be using the embedded JPG (with adjsutments applied) but the much smaller, not updated thumbview. I am not using "convert to linear" option when converting.

        • 1. Re: Problem with Apple Core Image?
          sandy_mc Level 3

          Core Image supports only a limited subset of possible DNG variations 

          e.g., for the Leica M8, etc. What exactly the subset is has varied 

          over time. But I'm not sure that's your problem - so far as I am 

          aware, there is no such thing as a thumbnail (or jpeg) that isn't 

          updated by Lightroom post adjustment. It's possible that what you are 

          seeing is the unadjusted raw data as rendede by Core Image, as no 

          Apple product will read any of the adjustments made in Lightroom.

           

          Sandy

          • 2. Re: Problem with Apple Core Image?
            Photo_op8 Level 1

            sandy_mc wrote:

             

            - so far as I am aware, there is no such thing as a thumbnail (or jpeg) that isn't 

            updated by Lightroom post adjustment. It's possible that what you are 

            seeing is the unadjusted raw data as rendede by Core Image, as no 

            Apple product will read any of the adjustments made in Lightroom.

             

            Sandy

             

            Sandy, thanks for your response, but I was hoping to get a response from an Adobe "watcher" (I know this is a U to U Forum). I posted my question here, since I know Eric Chan (Adobe engineer) pops into this forum and works on both DNGs and Lightroom. My uncertaintly continues in regards to-

             

            1. the LR command "Update DNG Preview & Metadata" implies that the embedded JPG is updated with any adjustments. Is there a thumbnail contained in the DNG AND is it updated by the command.

             

            2. DNG is a Adobe specification. Lightroom has an Apple application. I know Apple publishes some restrictions regarding CoreImage and DNG. Adobe works "closely" with Apple.

             

            3. Therefore, what does Apple CoreImage render (in Preview and other software that uses CoreImage)-(a) the thumbnail, (b) the embedded jpg or (c) the RAW data (unadjusted).

            • 3. Re: Problem with Apple Core Image?
              MadManChan2000 Adobe Employee

              Hi Photo_op8, the answer was hinted at by Sandy: you are correct that LR will update the embedded preview of the DNG, but Apple's OS uses its own rendering system (part of Mac OS) to show the previews in the Finder. This is completely independent of LR's rendering, or LR's embedded previews.

              • 4. Re: Problem with Apple Core Image?
                Photo_op8 Level 1

                MadManChan2000 wrote:

                 

                ..... but Apple's OS uses its own rendering system (part of Mac OS) to show the previews in the Finder. This is completely independent of LR's rendering, or LR's embedded previews.

                Hi Eric- So a software program (ImageBuddy) that uses Apple's CoreImage to render a LR "adjusted" DNG will not show an image from the DNG that has been cropped (landscape to portrait) and or enhanced (lightened for example).

                 

                --Dave

                • 5. Re: Problem with Apple Core Image?
                  MadManChan2000 Adobe Employee

                  >> ..... but Apple's OS uses its own rendering system (part of Mac OS) to show

                  >> the previews in the Finder. This is completely independent of LR's rendering,

                  >> or LR's embedded previews.

                  Hi Eric- So a software program that uses Apple's CoreImage to render a LR

                  "adjusted" DNG will or will not show an image from the DNG that has been

                  cropped.

                   

                  Will not. In general, LR adjustments (e.g., crop, fill light, etc.) are not

                  applied by Core Image. These types of adjustments are specific to each raw

                  converter.

                   

                  Eric

                  • 6. Re: Problem with Apple Core Image?
                    digitaloxygen Level 1

                    I am also very frustrated by CoreImage's (or whatever does the rendering) innabilty to display the jpeg previews embedded withing the DNG file.  I thought that was supposed to be one of the benefits of using DNG.  Using software like Lightroom or ACR the jpeg preview inside the DNG can be updated to reflect the post-processing that has been applied to the original RAW file.  The software creates a jpeg version of the processed photo and embedds that into the DNG which is what should be used as the thumbnail / preview in things like Finder or Windows Explorer on Windows.  Isn't that the point of having the embedded preview?

                     

                    I have found a 'workaround' though it's not very good.  It appears as though Finder and Quick Look just shows the original unprocessed RAW file as the preview.. BUT Cover Flow shows the proper fully processed jpeg preview that was embedded into the DNG via the processing software (Lightroom, ACR, etc)!!

                     

                    So you can see the proper embedded previews if you use the Cover Flow view in Finder... but that seems to be the only way to do it within the OS itself.

                     

                    BUMMER!

                     

                    Is there any other way to do this in the other Finder views?  Any 3rd party add-on or something?

                    • 7. Re: Problem with Apple Core Image?
                      digitaloxygen Level 1

                      I have confirmed that even in 10.6 Snow Leopard this is still an issue.

                       

                      Also choosing Metadata > Update DNG Preview & Metadata in Lightroom (or equivalent in other apps) is the only way to get the embedded preview in the DNG to reflect the Lightroom adjustments and be visible in Cover Flow.  Still no idea why this same preview is not displayed when using Quick Look or opening the file in Preview.  They are obviously reading/rendering the file differently than Cover Flow... very annoying but switching to Cover Flow is better than having no preview at all.