Current IPTC Digest

[GeorgeReis]

I have some files that have this field and show a value in it. What is this field, why does it get populated by data in some images and not others? What does it's value mean? Any help is really appreciated. These are with images from a Nikon D300, and I searched the tags for Nikon, as well as for XMP, IPTC, etc. and couldn't find anything.

[Phil Harvey]

You will find generated tags like this in the Extra Tags documentation, where it states:

MD5 digest of existing IPTC data. All zeros if IPTC exists but Digest::MD5 is not installed. Only calculated for IPTC in the standard location as specified by the MWG

- Phil

[GeorgeReis]

Thanks Phil. If I understand this correctly, should this field exist for any file that has IPTC data? If so, when is it generated - in camera?, only with software that supports it?

[Phil Harvey]

This is not a field that exists in the file.  It is a value that is computed by exiftool for files which contain IPTC information in the standard location.

This tag is used in conjunction with the Photoshop:IPTCDigest value to see if the IPTC has been changed.

- Phil