Further to this I received an email reply from FStop which requested images and on sending images the following.
“Thanks for sending the pictures. It looks like all these images do not have an XMP section for the tags but they do show in the properties section in Windows. When I add a tag then all of them are written to the file properly (using XMP). See attached. I am not sure how Windows Photo Gallery was writing them before but we only support XMP.”
This confirms that FStop only reads XMP tags.
On checking with Exiftool it appears that all the Windows Photo Gallery tags are in XMP. My problem was that because the original photos were 20MP images, I had used Faststone Resizer to reduce the size to something that I could fit comfortably on my tablet. Faststone helpfully moved the tags from XMP to EXIF. They are still in the file and show up in Photo Gallery before I copy them to the tablet but Exiftool shows that they are no longer in XMP format. Hence FStop can’t see them.
So the real culprit was the resizing. Using Irfanview to resize the 400 odd tagged images kept the tags in XMP format and when transferred to the tablet FStop successfully recognised the tags.
I apologise for my negative tone in earlier posts. FStop does appear to work as advertised as long as the tags are in XMP format and I did get a reply to an email from FStop support which helped me track the problem.
