If you have metadata related to a RAW file in a standard metadata format like XMP (Extensible Metadata Platform), then Capture One will automatically reload the metadata and merge the .XMP sidecar file with the metadata already created in Capture One.
Capture One can read metadata in the following four formats: Embedded EXIF, Embedded IPTC-IIM, Embedded XMP, and .XMP sidecar file. Note that only the .XMP sidecar files could be updated (modified).
XMP sidecar files
To activate or deactivate the Auto Sync Sidecar XMP option, go to Capture One -> Preferences on macOS or Edit -> Preferences on Windows. Click on the Image tab in the Preferences dialog box.
Then choose one of the three options from the Auto Sync Sidecar XMP drop-down menu in the Metadata section.
- Full Sync will create and update the XMP sidecar files with any metadata changes. Any information present in the XMP that is not present in Capture One will be loaded. It is a two-way sync.
NOTE: Using Full Sync when working with a large collection of new images can hinder performance. In this situation, it's recommended to use the "manual" sync commands such as Image -> Sync Metadata and Image -> Load Metadata in the main menu. This will achieve the same end result but without the background sync process slowing the processes down.
- Load will load the information from any XMP sidecar file into the .cos (session) or cocatalogdb (catalog). It will not update the XMP sidecar file with changes from Capture One. It is a one-way sync.
- None will disable the auto-sync.
Selecting the metadata set
Prefer Embedded XMP over Embedded IPTC toggles the preference when the two sets of data are present in the source image file; the legacy IPTC fields or XMP fields. You can find more info on the difference in this article: XMP and IPTC.
Prefer Sidecar XMP over Embedded Metadata toggles the preference between metadata information in sidecar XMP files (in either IPTC or XMP scheme) over the XMP information embedded in the source file.
NOTE: Above all, Capture One will never write metadata to source files; all metadata changes are done via proxy file.