I do believe, after looking at exiftool, the metadata can be updated by a command, like:
exiftool -tagsFromFile @ file.HEIC
see:
https://exiftool.org/exiftool_pod.html#Tag-operations However, some of the image files always displayed in macOS preview app as two thumbnails, whereas the original files, not ingested, always displayed as one thumbnail.
So I am not sure why this is but my solution to fix all these problems is to re-ingest the original files from the iPhone 16, as I have been keeping them around until things are stable. What I have been doing is the following:
1. Re-ingest the original images. This gives me two iPhone 16 images with one having a capital A appended.
2. With the metadata existing in the image file from a previous version (7239) of Photo mechanic, run the script, which will copy the metadata into the newly ingested image file and optionally rename it without the appended A.
3. This script preserves all the files by appending "_original" to the original files, and if everything looks OK, the original files can be deleted.
I would recommend using the latest production version of exiftool because they had some issues also with the iPhone 16 photos.
"IMPORTANT: Fixed issue which could corrupt HEIC images from newer iPhones under certain conditions when writing QuickTime:Rotation"
https://exiftool.org > History