IPTC/XMP Caption/Description vs IFD0 ImageDescription

[wywh]

How widely is IFD0:ImageDescription used to save a Caption instead using IPTC/XMP for that?

I noticed that iOS 15 now allows the user to write a Caption to a photo. AirDrop does copy that to a Mac and I guess also iCloud does the same (on the other hand, ImageCapture does not copy Caption to the Mac).

Code Select Expand

exiftool -a -G1 -s .
[IFD0]          ImageDescription                : Caption iOS åäöÅÄÖ.
[IPTC]          Caption-Abstract                : Caption iOS åäöÅÄÖ.

But when GraphicConverter 11.5.2 edits that IPTC Caption, it leaves the IFD0:ImageDescription intact and syncs only the added XMP-dc:

Code Select Expand

[IFD0]          ImageDescription                : Caption iOS åäöÅÄÖ.
[IPTC]          Caption-Abstract                : Caption GC.
[XMP-dc]        Description                     : Caption GC.

I never use that IFD0:ImageDescription anyway and I'd be tempted to ask GC author to add an option to delete it when updating IPTC/XMP.

- Matti

[StarGeek]

It does get used by a fair amount of higher end programs, including Windows and Lightroom.  It is one of the tags that is part of the MWG specs.  But it is often ignored by a fair amount of programs as well.

This is just my opinion, but I don't feel it's a very useful tag.  The IPTC and XMP description tags are much more flexible.  There are very few programs that allow direct editing of just that tag.  If a program can change it, it's always included with the IPTC and XMP description tags.

When it comes to EXIF tags, the only tags I ever edit are the three timestamps covered by AllDates and their corresponding time zone tags, Artist, Copyright, and the GPS tags.  And though I don't use them, Rating and RatingPercent would also be on that list.  I clear both ImageDescription and UserComment.  I leave all the rest of the EXIF tags untouched as those are all set by the camera and should rarely need to be altered.

[wywh]

Thanks for the reply and opinion.

GraphicConverter author informed me that GC already does have an option to clear that IFD0:ImageDescription (Exif Specifics > Delete Exif Image Description Tags) or sync it together with IPTC/XMP (Edit IPTC/XMP > Set Exif tags in addition (legacy)).