Hi Phil,
unfortunately the JPEG Comment won't do.
Using exiftool I wrote a comment to the jpeg file.
Then checked it like this:
exiftool -a -G1 00000049.jpg
------------------ snip ----------------------------
[File] Comment : 00000055.jpg 49.996021 8.663938, 00000036.jpg 49.9943629999306 8.664055, 00000115.jpg 49.996494 8.66523699986111, 00000123.jpg 49.996264 8.666156, 00000286.jpg 49.99588 8.66675
----------------- snap -----------------------------
So the comment data is OK.
But the jquery library I am using to access it is for EXIF data only. Not the JPEG Comment.
So how to add a tag to the GPS group?
Let's call the Tag "GPStest".
Thanks,
Jan