Edit 31May21 : Synology support recognise this as a bug. Their response is that unless a video has the following XMP tag then Moments will also look to the modification date not the creation date when ordering them after a copy event
all videos :
(In UTC %Year:%Month:%Date:%Time format)
quicktime videos :
So that leads to 2 questions
1) where can I find this Tag? Synology supprt tells me that some of my videos have it, and some don't, but can't explain to me where to find it
2) if I find the Tag, can I edit it? Can I bulk edit at the same time?
Can anyone recreate my bug : In copying .mp4 files from Moments User Photo Library to the Shared Photo Library, the Creation Date is overwritten by the modification date of the copy, and the Shared timeline view orders .mp4s then by the date of copy. This does not appear to be the case for .jpg, .mov, .heic etc.
So - if today I copy say a month's worth of files from my User Library into Shared, and look at the Shared Timeline view, everything looks OK apart from all the .mp4, which all are ordered into today, and not by creation date.
If anyone can recreate it, are there any fiendish workarounds?
I attach screenshots of a .jpg and .mp4 each in my User Library, and then the timeline view and metadata as seen in the Shared Library
Annoyingly, it is not consistent - an .mp4 from 2 years ago, when copied to the Shared, remains with the correct Creation Date and is ordered correctly in the Shared Photo Library
Even more annoyingly, a jpg from 2 years ago, when copied to the Shared, had its creation date modified and appeared in the Shared as today aaaarggghhh
oh fyi the use case : having a shared photo library of family stuff that both me and my partner can selectively add to, rather than having a shared album that only either of us can add to