Propagation of Date Subject Created - Variable Results

[PandDLong]

I am trying to setup a manual version relationship that will propagate some XMP tags from the Master to the Version. All works well except for 'Date Subject Created' (dates can be a metadata challenge).

Anyone successfully propagating 'Date Subject Created' through the Advanced Options?

Looking at TimeWiz it modifies two tags, so I put these two tags into the 'Advanced Options' of Versioning:

-XMP-photoshop:DateCreated
-XMP-exif:DateTimeOriginal

It works sometimes but usually not.  So I added the Composite date tag to the list and it worked more, but not always.  Then I added the EXIF tags, and that works most of the time and I can't find more tags so I think the list is complete and looks like:



But sometimes it still fails.   When it fails the result will have the XMP:Exif date propagating but not the XMP:Photoshop date - it seems to be "stuck".   

On a failed version - I run Metadata Analyst before the propagation - no issues with date tags.  Run after and the version has mismatched date tag errors.   Run TimeWiz and write-back - it is all clean again.

Context: these are JPEGs from scanning (prints, slides, negatives) and I use TimeWiz to set the 'Date Subject Created' for the master. In addition to this date, I propagate a few simple text tags (eg. title, description, etc) by selecting the options in the main Versioning dialog box.

So:

1. Should I need to be adding all these tags to the propagation list for Date Subject Created?  Is the order a factor?  Am I missing a tag?

2. Any ideas why it still fails sometimes?




Michael

[Mario]

IMatch maps XMP to EXIF using ExifTool's XMP2EXIF.args file, which works a lot of "magic".
IMatch also explicitly wipes many of EXIF tags before writing XMP, then calls XMP2EXIF to bring it hope.

See the examples in the help topic. You can explicitly set the XMP and EXIF tags from the dates stored in your database (make sure to use the correct format). The help has examples, e.g.

-exif:createdate={File.MD.createdate|format:YYYY:MM:DD hh:mm:ss}

[PandDLong]

Fresh day, fresh eyes!

Thanks for the information - it was helpful in sorting this one out.  

The situation where propagation always failed was:

   - the version had existing EXIF date tags
   - the master had no values for EXIF date tags

Using simple propagation, the version's existing EXIF date tags never changed and exiftool uses those tags to resolve conflicts between dates and the Photoshop tag would get changed to the EXIF value.   (Interestingly, the XMP:Exif tag remains as propagated and thus different than the corresponding EXIF tags).

Looking at my other files where I had "variable" results from propagation, shows a mix with and without EXIF date tag values.

I did some tests with propagating the EXIF tags (using variables to set the values as suggested) and including none, one or both of the two XMP tags.  To get consistent results, and for which the Metadata Analyst identifies no issues, it seems all 4 tags need to be propagated.  The following seems to always work:



A side learning is that propagation doesn't work for a null value - this was the source of the problem above and I tested this on a number of other tags.  ie. if the Master has no value for a tag, and the version has a value for that tag, propagation does not remove the tag value from the version.  Perhaps a note in the help?

Bottom-line - problem solved, onwards!

Michael