Star ratings:
Photo Mechanic doesn't see the star ratings applied by Expression Media. However, EM does see star ratings applied in Photo Mechanic.
The EM manual says the following about syncing catalog annotations to files. There may be an answer to your question in here:
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Sync annotations
Adding annotation information to media items in an Expression Media catalog does not embed annotations into the original file. The annotations only exist in the catalog.
To write or embed annotations into a file, on the Action menu, click Sync Annotations. This command lets you embed annotation information from the catalog into the original files. It also lets you import annotations, by rescanning files for metadata added outside Expression Media
with another application.
The synchronizing function applies only to annotations that are part of the IPTC, QuickTime, or XMP metadata standards. Custom metadata fields and Catalog Sets are now written to files as part of the XMP standard.
This function is particularly useful, because Expression Media lets you view, classify, and batch annotate a large number of media items and then exports the changes to the original files, saving hours of time opening and editing individual files. It is also useful for updating annotations that have been modified by applications outside of Expression Media.
Annotations that have been written into the file can be read by other applications that can read the IPTC, QuickTime, or XMP metadata standards, such as Photoshop or Graphic Converter.
Expression Media supports only the export of XMP metadata to .jpg, .tif and Photoshop formats.
Expression Media supports synchronizing annotations in the following Raw formats: Nikon, Kodak and Adobe Digital Negative (DNG) and Canon CR2 files. For more information,
Note: Synchronizing cannot be undone.
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