Question about sidecars

[Remco Viëtor]

On dimanche 22 octobre 2023 01:52:36 CEST Jay wrote:
> I'm using digiKam 8.0.0 and darktable 4.4.2 on Linux Mint 21.2.
> 
> I may have misunderstood the use of sidecars. I was expecting that a sidecar
> created in darktable would be readable by digiKam to show the changes I
> might have made in darktable and have them displayed in digiKam. And
> vice-versa as well. However, I'm not seeing the changes I make to each raw
> file in the other application, so think I may have misunderstood the
> ability to interchange .xmp files.
> 
> I have set digiKam to read and write to .xmp files, and have also set
> additional file extensions to RW2, my raw file extension.
> 
> Any assistance appreciated.
> 
> Jay Rutherford
The sidecars from darktable can be read by digikam (I use that feature 
myself). That said, reading an xmp file does not mean the reading program can 
*use* the information... 

Digikam can use the keywords, captions, etc. written by darktable (and vice 
versa). It cannot read the editing instructions from darktable. Some of 
darktable's modules have no equivalent in digikam, and for others you cannot 
be sure the parameters have the same meaning. 

Also, applications do not store a thumbnail in a sidecar file. So there is no 
way to transfer an edit from one program to another through a sidecar file, 
you will have to create an image file with the edits (export in darktable).

Nor is there an easy way to reuse the thumbnails from one program in the other 
(they use a completely different image formats and thumbnail organisations).

Remco