8 Replies Latest reply on Oct 5, 2017 10:19 PM by MagnusOfSweden

    Slideshow export process does not apper to use the RAW image file

    SimonBrettell

      On the Canon 5Dmkiv it's possible to recover 4 to 5 stops of detail out of the shadows when exposing for the highlights. However when you do this you have to have the original files attached (i.e. not be using smart previews) as once you push the shadows more than about 2 stops you get purple artefacts start to form in the darker areas of the image. When the original files are attached this problem does not appear (I'm guessing the difference in bit depth of the smart preview versus the RAW files causes problems).

       

      For exporting stills this isn't a problem but when I export a slideshow the purple artefacts are still present in the final video file, even though I have deselected the "Use Smart Previews instead of Originals for image editing" in the preferences. It looks like Lightroom does not refer back to the original RAW file but instead builds the slideshow from the preview image file.

       

      Has anyone else notice this, do you have a workaround?

        • 1. Re: Slideshow export process does not apper to use the RAW image file
          JimHess Adobe Community Professional & MVP

          The final video is not going to consist of the raw images. It will be compressed video and will not be able to tolerate as much dynamic range as the raw images are able to tolerate.

          • 2. Re: Slideshow export process does not apper to use the RAW image file
            SimonBrettell Level 1

            Hi Jim,

             

            I don't think that's  correct. The RAW files are 12 bit but when you export to JPEG they get remapped to 8 bit and don't suffer the same issue. The same should happen for the video file. You're right that it doesn't have as much dynamic range but it shouldn't matter as the values get re-mapped. You can see the effect in the image attached below . . . not the purple areas in the bottom corners. When exported to an 8 bit JPEG the image is fine as the data is rebuilt from the original RAW file. But when exported as a video it looks like the video is building from the preview images (hence why I get the purple patches) and not the RAW file.

             

            Capture.JPG

            • 3. Re: Slideshow export process does not apper to use the RAW image file
              JimHess Adobe Community Professional & MVP

              The raw file has to be converted for the slideshow. The slideshow, what ever is going to play it, it is not going to be able to display raw files. I don't know what is happening, and why you are getting the purple artifacts, but you cannot expect raw images in your slideshow. They can be used by Lightroom to create the slideshow and they probably are. But they have to be converted to pixels.

              • 4. Re: Slideshow export process does not apper to use the RAW image file
                MagnusOfSweden

                Hi,

                 

                just for clarification. Does this actually mean that whenever I press Play (or Preview) in the Slideshow module, and the selected files are (developed) RAW files, they will NOT be properly rendered according to the Quality setting in the slideshow module (e.g. regardless of what "preview" setting I have in the LR catalog)?

                 

                Do you mean that I first need to export the RAWs to JPEGs manually using the EXPORT dialog, and then manually select all these JPGs as input to the slideshow module? If so, what is it then that takes such a long time before the slideshow starts (after you press play in the Slideshow module)? I thought it rendered the RAWs files into proper JPEGs and passed them on to the slideshow engine, or what am I missing here?

                 

                If so, this means that, in order to look at slideshows in LR, based on RAW files with full quality, you have basically 2 options:

                1) always generate 1:1 preview files (taking considerable longer time and use more disc space than my normal strategy of using medium quality 2048)

                2) first export all RAWs to JPEGs, then select the JPGs before pressing Play in the slideshow module

                • 5. Re: Slideshow export process does not apper to use the RAW image file
                  Jao vdL Adobe Community Professional & MVP

                  Just to be clear, are your original raw files actually online when you do the slideshow? There are known issues with this sort of thing when you only have smart previews available. They just can't be pushed as hard as real raw files. When you export a slideshow, Lightroom should use the original raw files if they are available and only resort to the smart previews if the original raws are offline.

                  1 person found this helpful
                  • 6. Re: Slideshow export process does not apper to use the RAW image file
                    Jao vdL Adobe Community Professional & MVP

                    If so, this means that, in order to look at slideshows in LR, based on RAW files with full quality, you have basically 2 options:

                    1) always generate 1:1 preview files (taking considerable longer time and use more disc space than my normal strategy of using medium quality 2048)

                    2) first export all RAWs to JPEGs, then select the JPGs before pressing Play in the slideshow module

                    Neither of those are necessary. Lightroom should generate new jpegs from the raw files (or smart previews if the raws are offline) at the resolution needed for the slideshow on the fly when exporting a slideshow. Now the slideshow module has been buggy over the years and people have developed strategies to deal with this. The export to jpeg and then reimport and build a slideshow from that is an example of a workaround of a bug in an older version of Lightroom. You should not have to do this. Then again as said, the slideshow module remains quite buggy.

                    1 person found this helpful
                    • 7. Re: Slideshow export process does not apper to use the RAW image file
                      MagnusOfSweden Level 1

                      My RAWs are fully local.

                       

                      Super thanks for that information. I'm so used to my old LR4, and I start to understand a lot has happened since then...new features (bugs) and everything ;-). The performance is a bit worse compared to LR4, but again with 40Mp RAW files I still think processing is fairly impressive and culling still works way better than most other software I tried (two monitors and the combination of views per monitor).

                      • 8. Re: Slideshow export process does not apper to use the RAW image file
                        MagnusOfSweden Level 1

                        KUDOS for the fast reply. Now I know, so then I can post my first bug report too ;-)