Try this:

- Phil

I apologize. I now see that it works if I do what you said. (use < instead of =) Thanks again.

It is simple:

"=" sets the value of a tag.

"<" copies the values of other tags.

Enhancements to the "<" syntax (see the -TagsFromFile section of the exiftool application documentation) allow a string containing tag names prefixed by "$", which is what we are doing here. Also, a special "now" tag is provided (see the Extra Tags documentation) to represent the current date/time.

- Phil

Regarding "=" vs. "<", the difference, as I understand it, is what is permitted in the "expression" on the right side. In addition to copying a tag, the "<" form allows a kind of string expression using filename variables (%f etc.) and tag names ($tag), but the "=" form only allows constant values on the right. Is that correct?

Is -TAG<=FMT equivalent to -TAG<FMT? Or is "<=" only used in the form -TAG<=DATFILE to set a tag from the contents of a file?