I have many photos in shared album that are duplicates.
MacBook Pro 13", macOS 10.15
Have you shared the same photos twice? Shared albums are different from standard albums. Standard albums are checking for duplicates and you can add a photo only once, but shared albums are allowing you to add the same photo over and over again.
If you only use My Photo Stream and Shared Albums, you do not need paid cloud storage. These services are free.
But you should not use shared albums to save the photos in iCloud. Shared albums are only storing the photos in a lesser quality - the size will be reduced to 2048 pixels at the longest edge and some metadata will be removed. Use iCloud Photos instead. I am using shared albums only to share selected photos with friends and family, and there have never been duplicates in my shared albums.
I have not tested any other cloud storage other than iCloud Drive and iCloud Photos, because it has been working well for my library, so I cannot recommend any other service based on my experience, sorry.
No I have not shared them twice, I'm sure about this. Also some photo inside shared album that i have not created but just shared with me appear in my photo library without any reason and only some. I'm really bored of this problem also because i pay extra space on iCloud do you know some good service to store photo on mac with also an app fro iphone?
Sorry I'm not good to explain my self maybe, I know that my english is not good.
I use Photo to store my photos (the default app for macOS), I pay because I want the Photos on the cloud the 200Gb option. I use shared albums just to share photos with friends that's all, and some of them use shared album to share some photo with me, I never save photo on the shared albums.
That's all fine, then, sorry, that I misunderstood your post.
But I have never seen duplicates in a shared album, unless the same photo has been added repeatedly. That is a mystery for me.
Duplicate photos of shared album
