4 Replies Latest reply on Jan 23, 2009 1:46 PM by MadManChan2000

    Canon 5d2 DNG +custom profiles = bad preview in Bridge?

      I'm using DNG Profile Editor (1.0.0.39 Beta 2) to make custom profiles for my new Canon 5D Mark II, and then using DNG Converter (5.2) plus Photoshop CS3 Bridge to process images. All on Windows XP.

      After my 5D2 custom profiles were in place I noticed that the image preview in Bridge CS3 was "bad." The Bridge preview is very blurry and does not update when changes are made to the DNG file via ACR. For example, if I change exposure in ACR and click "Done" or "Open in Photoshop, the change is saved OK in the DNG file but the Bridge preview remains the original blurry image.

      Took a long time to figure this out because I did not immediately associate the problem with the creation of custom profiles. Older 5D2 DNG files previewed OK in Bridge, as did DNG files from my other cameras. I even re-converted some old camera raw files to DNG and they previewed OK in Bridge. There are custom profiles in place for those older cameras.

      I spent a lot of time on the usual suspects - purging cache, reseting preferences. All to no avail. Then I removed all my custom profiles and deleted the index.dat file. Ran DNG converter again to make new DNG files from the 5D2 raw. Now the Bridge preview was OK. Then I restored my custom profiles and converted raw to DNG again, getting bad Bridge previews again. Yet the previous converted files would still preview OK in Bridge.

      My conclusion: The DNG converter is using camera profiles during the conversion, and in the case of 5D Mark II raw files is creating an error. I'm guessing it is putting an embedded jpeg in the DNG file that somehow confuses Bridge.

      I've repeated the tests many times now. I've changed the DNG Converter "jpeg preview" preference to none, medium and full. For the 5D2 files I get bad Bridge previews on all settings. But I get good Bridge previews on my Canon 20D and Canon 1Ds DNG files regardless of any settings. Regardless of the presence or absence of custom profiles, regardless of the jpeg preview size, regardless of the ACR default settings.

      So I'm hoping the Adobe team can take a look at this. Or anyone willing to confirm or deny my tests. I don't have an easy way to post a DNG file, but could email one of my "bad" ones to anyone willing to take a look.
        • 1. Re: Canon 5d2 DNG +custom profiles = bad preview in Bridge?
          Level 1
          The lack of response to this post forced me to keep testing. Now I've more closely pinpointed the problem and found an easy work around. First some background.

          ACR camera profiles are stored in two places. The Adobe supplied profiles are in:
          C:\Documents and Settings\All Users\Application Data\Adobe\CameraRaw\CameraProfiles
          and your custom profiles are in:
          C:\Documents and Settings\yourusername\Application Data\Adobe\CameraRaw\CameraProfiles

          Adobe Camera Raw, and it turns out the DNG Converter, both build an Index.dat file in this last folder. Apparently this index is built by scanning both camera profile directory trees and building a list of all the profiles it finds. It then sorts that list alphabetically by the profile name that is embedded in the file, not the Windows file name.

          The "Adobe Standard" profile for a camera has a file name like "Canon EOS 5D Mark II Adobe Standard.dcp", but embedded in that file is the profile name of just "Adobe Standard". That's why only "Adobe Standard" shows up in the drop down list of profiles in ACR. And that's why "Adobe Standard" appears before "Camera Faithful", which appears before "Camera Landscape". It's alphabetical order.

          Now, when you create a custom profile with the DNG Profile Editor, the "Export" function puts "Canon EOS 5D Mark II" on the front of the name. If you are an idiot, like me, you type over all that with something simple like "5D2 Bouce Flash" for the profile name. But wait, "5D2 Bounce Flash" sorts alphabetically before "Adobe Standard" and appears first in the ACR drop down menu. Sounds OK so far.

          But then the magic occurs. The DNG converter uses the camera profiles. It actually accesses that Index.dat file, and if it does not exist, the DNG converter will rebuild it, just like ACR. Why it does that I can't imagine. Seems to me that the DNG converter should be simply converting raw to DNG and passing the EXIF and embedded camera jpeg along as is. What need does it have for camera profiles?

          Anyhow, if that 5D2 profile is first in the list due to its alpahbetical name, the resulting DNG file will confuse Bridge. Bridge will display a fuzzy preview and will never update that preview, or the thumbnail, when you make adjustments in ACR.

          But if you name the 5D2 custom profile such that it sorts alphabetically after "Adobe Standard", then all is OK. The DNG files can be previewed and thumbed OK by Bridge. So I named my custom profile "My 5D2 Bounce Flash", a simple workaround.

          Now I can move on to more important things. Like generating a good custom profile for the 5D2. So far the Adobe Standard profile beats anything I've generated. Especailly if I remove that curious Point Curve which can sometimes muck up the shadows.

          And now that Bridge previews are "OK" I can work on the mystery of why Bridge Previews of 5D2 DNG files do not match the previews of their equivalent TIF or PSD files. If you're curious you can see samples and read more about that here: http://forums.dpreview.com/forums/read.asp?forum=1032&message=30748423
          • 2. Re: Canon 5d2 DNG +custom profiles = bad preview in Bridge?
            MadManChan2000 Adobe Employee
            > But then the magic occurs. The DNG converter uses the
            > camera profiles. It actually accesses that Index.dat file,
            > and if it does not exist, the DNG converter will rebuild
            > it, just like ACR. Why it does that I can't imagine. Seems
            > to me that the DNG converter should be simply converting
            > raw to DNG and passing the EXIF and embedded camera jpeg
            > along as is. What need does it have for camera profiles?

            The reason is that camera profiles get embedded into DNG
            files. That way, the profile remains available when
            processing the DNG even if (1) you were to delete the
            external .dcp profile from the disk, or (2) you were to
            copy/move the DNG to another machine that didn't have the
            external .dcp profiles installed.

            The DNG Converter has had this behavior since the beginning.
            Older profiles like ACR 2.4, ACR 3.3, etc. were also
            embedded into the DNG. The only difference is that those
            older profiles were built into the DNG Converter (instead of
            being external files sitting elsewhere on disk).

            Eric
            • 3. Re: Canon 5d2 DNG +custom profiles = bad preview in Bridge?
              Level 1
              Thanks again, Eric.

              I understand that camera profiles become embedded in DNG files by ACR when you select and set a profile. As do any other settings the user makes in ACR. Makes sense. If someone is using true raw instead of DNG, then ACR stores those settings in the xmp file (or cache).

              I can see a little logic in why the DNG converter adds a camera profile to the initial DNG file, but how does it pick the profile? It appears to just pick the first one in the "alphabetic" list, which may or may not be the one the user has chosen as default for the camera. But no problem, ACR will overide the choice the DNG converter made the first time the file is brought into ACR.

              The point remains that Bridge can not properly display previews and thumbs for Canon 5D Mark II DNG files IF (and a Big IF) the initial camera profile embedded by the DNG Converter is a custom profile created by the DNG Profile Editor. And that DNG file is permanently spoiled. If you bring it into ACR, set the profile to "Adobe Standard" and save it, then it still previews incorrectly in Bridge.

              Sounds like a bug to me. But maybe I'm still confused or maybe my system is messed up.

              So someone please do me a favor. Here are links to a Canon 5D Mark II raw file. Please download the DNG version and view it in Bridge. Does the preview look very blurry to you? Open the file in ACR. Does it look OK there? Give it a big exposure change and just click "Done" to update the DNG. Then preview it again in Bridge. Does the preview show the change in exposure? Or is it still the same blurry preview?

              DNG file = http://www.savefile.com/files/1978938
              From this original raw = http://www.savefile.com/files/1978913
              • 4. Re: Canon 5d2 DNG +custom profiles = bad preview in Bridge?
                MadManChan2000 Adobe Employee
                > I can see a little logic in why the DNG converter adds a
                > camera profile to the initial DNG file, but how does it
                > pick the profile?

                It picks the profile using the same logic that Camera Raw
                does:

                - If the raw file has settings (e.g., in a sidecar xmp) then
                the profile specified in the settings will be used, unless
                it cannot be found on the system (e.g., you removed the
                profile).

                - If that doesn't work, then the per-camera default profile
                will be used, unless it cannot be found on the system.

                - If that doesn't work, then the first available profile for
                this camera will be used ("first" in this context means in
                increasing lexicographic order).