Kenneth Cohen1 wrote:
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I thought that all my original photos are kept in the library, and that shared albums get their photos from the library. And that deleting a photo from a shared album does not affect the original.
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That is a misunderstanding. This is true for standard albums, but Shared Albums are not a part of the library, the are just shown in your library. When you share photos in a shared album, Photos is creating a copy for the shared album, optimized for sharing. It will be downsized to a reasonable size and many metadata will be stripped, so you do not share accidentally some confidential information. Once the photo is shared, the photo will remain the same, even if you modify the original in your library. When you delete the photo you shared from your library, the shared copy will remain in the Shared album.
Which system version is installed on your Mac? In the older system versions we cloud ctrl-click a photo in a Shared album and use the command "Reveal in Library" to find it, if it has still been in our library, but that is no longer possible on macOS 15 Sequoia. I am not sure, which system version changed this.
You could try to import the missing photos from your shared album back to your library to have at least these copies. If the originals are still in your library you will find them sooner or later in the Duplicates album and the remove the copies you saved from the Shared album.
Also, photos you added recently to the Shared album will be tagged with the correct date. If you look at the date and time, you will know where to look in your Photos Library to find the original versions.
How to save photos from a Shared Album: If Shared Albums aren't working - Apple Support (BW)
How to back up a shared album
Shared Album content isn't automatically backed up. When shared, photos are reduced to 2048 pixels on the long edge, panoramic photos can be up to 5400 pixels wide, and videos are delivered at up to 720p resolution. To have a copy in its original resolution, keep your originals in your photo library. If you delete content from your photo library after uploading to a shared album, you no longer have access to the full resolution file.
If you want to save a photo or video from a shared album, add it to your photo library.
- On your Mac: Control-click the photo or video, then select Import.
Any comments or likes attached to a photo or video in a shared album aren't saved with the photo or video.
