Today’s Question: Which of the rating systems (ratings, flags, and color labels) would be available to a user that is not accessing the photos from Lightroom Classic such as if the file types were all changed to JPEG when exporting?
Tim’s Quick Answer: Star ratings and color labels can be preserved in metadata outside of Lightroom Classic as long as steps are taken to actually include that metadata. Pick and reject flags assigned in Lightroom Classic, however, are only available within the catalog and will not be included in metadata for photos accessed outside of Lightroom Classic.
More Detail: By default, the metadata you add to photos in Lightroom Classic is only saved within the Lightroom Classic catalog. However, there are options for including standard metadata values in photos beyond the Lightroom Classic catalog.
However, information that is not part of a metadata standard cannot be included in the metadata for your source photos, and instead is only available within the catalog. This includes pick and reject flags, collections, virtual copies (unless they are exported as new images), and the history within the Develop module.
The first option for including standard metadata in the source image files is to save that metadata to the source images from within Lightroom Classic. You can manually save metadata to the source images by selecting the images and choosing Photo > Save Metadata to File(s) from the menu. You can also enable the option to have metadata updates saved to source files automatically by turning on the “Automatically write changes into XMP” checkbox on the Metadata tab of the Catalog Settings dialog.
The second option is to export new copies of the source images with the option enabled to include metadata. In the Metadata section of the Export dialog in Lightroom Classic you can choose which metadata to include in the copies of the photos you’re exporting. If you select “All Metadata” from the Include popup, for example, all of the information in the standard metadata fields will be included in the exported copies of the photos.