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In my workflow, I import my photos into LrC and then cull the "bad" ones. For the "really good" photos, I then crop, denoise, sharpen, and sometimes scale using Photo AI (via the plugin). Photo AI accepts my Sony ARW file and returns a DNG file. I then edit the DNG file in Develop.
Recently I discovered that through Sep 13, 2023, for all photos I edited, both the ARW and DNG files, when in Develop, show the Profile as Camera ST. I can click Camera ST and get a popup where I can click Browse. That brings up a menu where I see Camera Matching, with ST selected.
I have no idea exactly what all that means nor how all that happens, but it seems correct.
After Sep 13, I worked on another project for a few weeks. I started processing photos again Oct 23, 2023. All photos from then on behave differently. The ARW in Develop behave as described above. But now the DNG behave differently. In Develop, the profile still shows as Camera ST, but underneath is a warning/error saying "! Profile missing". If I click Camera ST and then click Browse, the resulting menu does not contain Camera Matching!
There are 3 things that are likely different and 1 thing definitely different between pre- and post- gap processing:
As I hinted earlier, I don't know if any of these conditoins could cause the difference in behavior. I did a bit of browsing of the metadata assoicated with the files and could find nothing that seemed to distinguish the pre- and post- behavior.
While I cannot visually see any impact from the difference all this, since I don't understand how the profile gets determined, I don't konw if it matters.
Any help welcomeed!
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Comparing the metadata in the two files, I found the cause:
The newer version of Topaz Photo AI (2.0.6) is writing an invalid value into the EXIF field UniqueCameraModel. When I use Exiftool to change it to "Sony ILCE-1", the profile is no longer missing.
That field is not industry-standard, and it isn't documented in the DNG spec. But LR and Camera Raw apparently use it, rather th
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I should have included 2 things that have not changed: all the photos mentioned were shot with the same camera and lens.
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There are several possible causes of this. The most efficient way to troubleshoot this, rather than play 20 questions and make likely guesses, is to provide sample files for us to examine. Select a DNG that shows the Profile Missing message and one DNG that doesn't. Upload both to Dropbox, Google Drive, or similar service and post the sharing links here. With those, I can provide an accurate answer.
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[This post contains formatting and embedded images that don't appear in email. View the post in your Web browser.]
Comparing the metadata in the two files, I found the cause:
The newer version of Topaz Photo AI (2.0.6) is writing an invalid value into the EXIF field UniqueCameraModel. When I use Exiftool to change it to "Sony ILCE-1", the profile is no longer missing.
That field is not industry-standard, and it isn't documented in the DNG spec. But LR and Camera Raw apparently use it, rather than the industry-standard fields, to identify the camera model. Go figure.
Because the camera model was recorded wrong, LR / Camera Raw couldn't find the camera-matching profile "Camera ST".
Try downloading the latest version of Topaz Photo AI (2.2.0) to see if that fixes the issue. If it doesn't, you'll have to contact their support about the bug.
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Thanks so much. I contacted Topaz support over the weekend, but you've provided the answer. I'll get it to them.
I am often puzzled by the use of non-standard fields, and even more so by modifying them when they should be a pass-through. As you said, go figure.
Thanks again.