I plan to create a shared photo library with my wife. Our two libraries are 90% identical. Will the shared library contain mostly duplicates, or is the system smart enough to identify & overlook the duplicates?
When you are merging two libraries in iCloud Photos, Photos will scan for duplicates when you are merging an additional library into your existing iCloud Photos Library, so each photo will only be stored once in iCloud Photos.
But this seems to be different, when two users are contributing to a Shared iCloud Photos Library.
I have just tested with my own Shared Library. When I shared photo to the shared library, that already has been added to the shared library from a different Apple ID, it will be added to the shared library without a warning about the duplication.
However, the Duplicates Album will show you the duplicates, once the library has been scanned. Once you are using a Shared iCloud Photos Library, the Duplicates album will only be shown, when you are viewing both libraries, the Shared library and your personal library together. So you can see, which photos in your personal library are already in the Shared library and can avoid to share them again.
When you are merging two libraries in iCloud Photos, Photos will scan for duplicates when you are merging an additional library into your existing iCloud Photos Library, so each photo will only be stored once in iCloud Photos.
But this seems to be different, when two users are contributing to a Shared iCloud Photos Library.
I have just tested with my own Shared Library. When I shared photo to the shared library, that already has been added to the shared library from a different Apple ID, it will be added to the shared library without a warning about the duplication.
However, the Duplicates Album will show you the duplicates, once the library has been scanned. Once you are using a Shared iCloud Photos Library, the Duplicates album will only be shown, when you are viewing both libraries, the Shared library and your personal library together. So you can see, which photos in your personal library are already in the Shared library and can avoid to share them again.
Thanks! I tried it and so far find that Duplicates (which is slow! with large libraries) so far is finding some but not all duplicates. Also, there are limits to one user's ability to delete duplicates that are in the other user's library, so it's a significant issue. I'm surprised that the Shared Library feature didn't consider this... I'd think it would be common when couples/families want to start sharing libraries.
I have stopped using the Shared iCloud Photos Library for sharing, because I did not like, that the photos I am sharing are moved out of my personal library.
I would have preferred to create a separate shared library in addition to my personal library. As it is now, my most important photos are removed from my most important library, my iCloud Photos Library, the only library I can sync across all my devices with iCloud Photos. I wanted to keep my personal library as it is, not remove my best photos from it. While I have been using the Shared iCloud Photos Library I have duplicated all photos before sharing them and only shared the duplicates. I wanted to be sure, that I kept a copy of my photo with the adjustments I had applied and all metadata I had added, before the photos have been moved out of my library into the hared library, where everyone could modify my adjustments and the captions I had assigned, as I had invested a lot of work into editing my photos to my liking.
Currently I am using the Shared iCloud Photos Library to have two libraries in iCloud on all my devices, a private library and a public (shared library, shared one with myself) that I switch to, when I want to show my photos to someone.
what happens when merging/sharing two photo libraries that contain duplicates
