There are already options for selectively write (and read) metadata in selected namespaces for comment (description), tags and rating. Such an option is missing for caption, which is written in all available namespaces. It should be possible to limit that one similarly. Specifically, I want to preserve the 'dc' namespace only.

The same should be possible for image information metadata, which is written to sidecar files. digiKam writes a bunch of exif and tiff namespace parameters, which I find unnecessary as they can always be read from a raw file. An option to exclude those namespaces would be handy as well. Of course, excluding exif should not disable writing GPS coordinates if they are set.