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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
> 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).
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
> 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
- 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
- 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).