PM removes EXIF:Artist and EXIF:Image Description fields

[primer]

I used EXIF Tool to write a series of tags from a csv file. Among them were EXIF:Artist, EXIF:Image Description, and EXIF:Copyright.
I then ran "exiftool -a -u -g1 filename.tif" and confirmed that all of the tags from the csv had been written correctly.

I then loaded that image in Photo Mechanic, and clicked on the "i" in the bottom left corner, and added 5 test keywords to the image, and then clicked "OK"
The test keywords were written to the image.

I then ran "exiftool -a -u -g1 filename.tif" once again, and discovered that the EXIF:Artist and EXIF:Image Description fields had been stripped. They were no longer there. However, the EXIF:Copyright tag was still there.

Why is Photo Mechanic stripping some EXIF tags (and not others) and how do I stop it from doing so?

EDIT: PM also stripped the UTC offset from EXIF:ModifyDate, though it left it alone in other fields such as IPTC:ReleaseTime and IPTC:TimeCreated

[Kirk Baker]

Please read this post and answer as many of its questions as you can:

http://forums.camerabits.com/index.php?topic=4688.0

Thanks,

-Kirk

[primer]

Hi, yes I should have included that info.. I'm running PM 4.6.8 under Windows 7 64-bit.

[dennis]

Here is what is going on.  Photo Mechanic looks for things like Caption, Byline, and Copyright from IPTC/XMP.  If it doesn't find it there then it assumes those fields don't exist and then when it updates a TIFF (or TIFF-based RAW) file then it updates the corresponding Exif fields (Image Description, Artist, and Copyright) to match what it thinks the values are in the IPTC/XMP.

Since you only wrote the values in Exif then PM doesn't recognize these.  The standard place for these fields and the many others is IPTC/XMP.

I suggest you use PM and the IPTC Stationery Pad to update your photos.  This is a lot easier than using a command line exiftool statement.  Plus, PM would then also put the data into the Exif in addition to updating the XMP (and IPTC if desired) for your TIFF files.

You should be able to revert your photos to the state before PM touched them by using the "Revert TIFF-based RAW" command from the Tool menu (even though I assume this is a real TIFF file and not a RAW file like CR2 or NEF etc).

HTH!

--dennis

[primer]

I used EXIF Tool to write a series of tags from a csv file. Among them were EXIF:Artist, EXIF:Image Description, and EXIF:Copyright.

When I wrote the tags using EXIF Tool, I didn't only write EXIF tags. I wrote them to IPTC and XMP as well... IPTC:By-Line, IPTC:Caption-Abstract, IPTC:Headline, IPTC:ObjectName, IPTC:Writer-Editor, XMP:Caption-Writer, XMP:Creator, XMP:Headline, XMP:Title, and many others, were all written in EXIF Tool prior to PM stripping the EXIF Tags.

If it is as you say, that there were blank IPTC and XMP tags then which IPTC and XMP tags, specifically, need to have been written for PM to not strip EXIF:Artist, EXIF:Image Description, and EXIF:Copyright tags?

I suggest you use PM and the IPTC Stationery Pad to update your photos.  This is a lot easier than using a command line exiftool statement.

So far I've found that doing the bulk of the tagging via EXIF Tool has been very smooth. In two days' time I was able, using a combination of grep and REGEX, to prepare a CSV file containing over 100 EXIF, IPTC, and XMP tags and was able to tag 17,000 images with my core tags, so I'm perfectly happy with using EXIFTool to do the bulk of the tagging. I do, however, rely on PM for applying the keywords because it helps with sorting and structuring my keyword lists..

I'm more than willing to test your theory by populating the specific corresponding IPTC and XMP tags and then seeing if PM again strips the EXIF, but I need to know which ones, because I'm pretty sure I'm already including *all* the relevant IPTC and XMP...