How to append a string to a tag with exiftool
Use this:exiftool '-Comment<$Comment Stuff added to comment' dst.jpg
Since you're copying a tag as well as adding stuff, you need to use the copy tag syntax "<" instead of the assign value syntax "=".
Use this:exiftool '-Comment<$Comment Stuff added to comment' dst.jpg
Since you're copying a tag as well as adding stuff, you need to use the copy tag syntax "<" instead of the assign value syntax "=".