Saw this old post for some reason and it got me thinking:
http://forums.camerabits.com/index.php?topic=8000.msg38295#msg38295I was not aware that PM would write to, and possibly erase, the Artist and Image Description in EXIF field groups in a raw file. The various write settings for raw files in Preferences specifically reference IPTC and XMP as embedded write options but no mention is made of writing to or deleting EXIF fields. However, after testing, this is indeed correct. If you are not careful, you may have unintended results. In the case of the original poster, they probably accidentally had the tiny x marked in those blank fields while adding keywords to the keyword field USING IPTC Stationary Pad.
I posted this because I had not seen this discussed much other than this short post. Maybe it has. I always assumed those fields would not be changed by PM. But I was wrong.
UPDATE: Further testing shows that PM does write and delete to 2 Exif fields: Artist and Image Description. It also creates a duplicate version in XMP-dc fields. It does not change the original Exif copyright information but writes new data to XMP-dc if changes made in PM (so a conflict is allowed). It will show the version from XMP-dc (latest) if there is a conflict. It does not make any change to Exif User Comment field - despite the fact that some editing programs such as Capture NX-D feed this data into a field called Image Description.
Probably much ado about nothing but it may help some.
