Tags and JPEGS - reload wrong tags - suggestions?

[Remco Viëtor]

On mardi 21 mai 2024 13:59:33 CEST digikam at boeziek.nl wrote:
> I have indeed selected the option to be compatible with commercial programs.
> However, the RAW and JPG names are not identical as I continue numbering.
> So PHOTO1.RAW, PHOTO2.JPG, PHOTO3.RAW and each with an accompanying .XMP
> file, as in PHOTO1.XMP, PHOTO2.XMP, PHOTO3.XMP.
> 
So you could run into issues with tagging, titles and descriptions not being 
synchronised between a raw file and its corresponding jpeg, when using 
sidecars. 
However...
> If the image files had the same name, like PHOTO1.RAW and PHOTO1.JPG then
> the PHOTO1.XMP would always be correct as it is written when adjusting the
> RAW file.
this is not correct: one of the things that can be stored in the sidecar file 
is the order of editing operations performed on the image. The semantics of 
that is different between a raw file and the resulting jpeg:
- for the raw file, it describes the operations *to be* performed;
- for the jpeg, it would describe the operations that *have been* performed 
*on the corresponding raw file*.

In addition, there are some issues when creating several versions of a given 
raw file, some tagging can be off, and gestion of date stamps gets 
complicated...
> So somehow, you want either to ignore .XMP file when there is no RAW file
> with the same name or a better way I think would be to force to write to an
> existing .XMP file when you update a .JPG file.
> 
Digikam, and darktable (perhaps others as well) have chosen a different 
solution: just use the filename+ extension of the image file as the prefix for 
the sidecar file, and add the .xmp extension. That solves the issues mentioned 
above. 

So if you do not need to maintain compatibility with lightroom, capture one, 
etc., one solution might be to import with the LR-style sidecars, then close 
digikam and destroy the LR sidecars. The metadata will be in the database, so 
you can always recreate the "digikam-style" sidecar files.