Big Sur Does Not Support Photos Library On NAS

WDI wrote:

Oh, and there is no going back because Big Sur changed the library when troubleshooting the issue so it will no longer open in Mojave Photos app...

The only way to downgrade the library losslessly is using iCloud Photos. If you would just upload the photos once, to iCloud Photos Library, temporarily for the conversion, and then download again on Catalina to a new, empty library, you will have a perfect downgrade to the Photos 5 format. See: Downgrading a Photos Library to a Previous Version of Photos with the Help of iCloud Photos

But surely you have made a backup of your library before you upgraded to Big Sur? Restore the Photos 5 version from your backup to have a Catalina version.

Without a backup and without iCloud Photos you will have a hard time to get access to your Photos Library on Catalina, because we can no longer recover the photos unchanged from the Photo Library package. We need Photos to retrieve the photos from the library. The package contents is no longer easy to read without the help of Photos to decode the filenames: How Photos 5.0 on Catalina Manages original Files and Filenames

You should be able to export them. Mine never go into Photos in the first place.

1. I get a photo (from whatever source) either by plugging in a card reader or air dropping it, downloading it.
2. The photo is on my desktop.
3. I check if it needs any "adjustments", "editing" or whatever.
4. For that you can use Preview or any third party photo editing app (my iMac still runs Sierra > therefore I am still using Aperture. So, if needed, I do some "enhancing".
5. I rename the photo from xxxxx.jpg to something that makes sense to me: beachtrip 2019 (if more than one, I add a number in the description)
6. I created a new folder in Finder and named it "Photos"
7. Moved the folder into my Documents > my Docs

Always creating new sub folders for the current year/trips/friends/whatever. There is no limit.

Since that is in your Documents folder, it does not have a "library" or is not associated in any way with the Photos app. The pics are simply photos stored in your user folder.

FWIW, that folder "my Docs" contains anything and everything important to me in it: includes banks stuff, financial info, any letters I've written, and the list goes on. It is my most important folder on my Mac. It gets backed up every time I make a change/add something and I have a copy of it on 5 different external devices - just in case. It is also not associated with any library or app, so i can simply copy/paste/drag it to a disk for backup. It is currently at 38 GB of space.

With Photos on High Sierra I kept my Photos Library on a Synology NAS and all worked fine

You may not have noticed if the library got damaged. apple has always been warning against putting the library on a network share, because the application has not been developed to support a network database. Database transactions over network can result in dataloss, if the database is not synchronising the transactions. You have probably been very lucky.

Apple's Support documents have contained this sentence since Photos has been released in 2015:

"Apple doesn't recommend storing photo libraries on external storage devices like SD cards and USB flash drives, or drives that are shared on a network."

Move your Photos library to save space on your Mac - Apple Support

If you want to store your photos and videos on NAS but also enjoy the editing and other features that Photos offers, here's one possibility:

1) Export everything from the Photos library into a folders and sub-folders structure (years/months), and save on NAS (Photos' native export function will put everything in one big folder. If you want to retain organization, Photos Takeout app does it.)

2) When the export is complete (May take a while), delete the photos and videos from Photos (Probably better to create a new library, and backup the current one somewhere before deleting it).

3) Go to Photos Preferences, General, and uncheck "Copy items into the Photos Library".

4) Import the items on NAS back into Photos as referenced files.

This would solve the storage issue and give you scalability, but a few things to bear in mind:

1) You'll need to ensure proper setup between your Mac and the NAS

2) You'll need to remake the albums. You could extract a list of albums and file names of the photos in each

3) You'll need to leave special file types e.g. live photos and bursts behind in Photos - they can't be exported

4) You should be aware of the disadvantages of referenced files and work around them

Just from the point of view of historical accuracy, Photos - and indeed, iPhoto and Aperture that preceded it - has never supported having the library on a NAS. This is not new. There are two strikes against it:

1. The disk format of the NAS is wrong. These devices are essentially a headless Linux computer and you're trying to store a Mac database on a Linux computer. It's just not built right for that.
2. Photos, nor its antecedents, does not have the code to negotiate a network share, and especially to do so where dropouts, even brief ones, are not uncommon. So as well as a performance hit you also run a real risk of dataloss.

Ultimately, Photos is a freebie and you get what you pay for.

It is interesting to compare with apps you actually pay for. Photo Supreme can host its library on a NAS but they point out that there can be a speed hit. Other apps - such as Lightroom Classic, Capture One - will host the file storage on a NAS but strongly recommend that the catalogue or database is retained on the start-up disk. And both point out that performance will be at the mercy of the quality of the network. OnOnePhoto Raw might hold out the best hope as it doesn't have a central catalog and might be worth checking out, but I can see how the quality of the network will have a major impact on performance.

Theoretically you could use Photos in Referenced mode, and store the masters on the NAS but I would not do it. Photos has no tools for properly running in referenced mode, and adding a Network location into that mix is just asking for trouble.

You can either

• go back to Big Sur and keep Catalina installed on a second volume, so you can use the older applications, until you have Big Sur compatible updates
• go temporarily back to Big Sur to rescue your Photos Library by uploading it to iCloud Phots, then go back to Catalina again,
• or go temporarily back to Big Sur to rescue your Photos Library by exporting your originals with the original filename from your Big Sur Photos Library, also the edited versions with the metadata then go back to Catalina again,
• or restore the most recent Catalina backup of your Photos Library (with a different name). Then try to extract the newer photos from the current Big Sur library by opening the package content and searching the "originals" folder for all files with the Kind: image and sorting it by "date added". This will allow you to extract the newest photos.

This won't answer your question, but it may be worth a thought for the future:

I have never appreciated Photos' (or iPhoto) library system/file management, so I have never used the app. I don't like "places" or whatever categories there are available. Instead, I created a simple folder "photos" within my Documents folder. It has many subfolders and that is where all of my photos reside. I manage the filing system, decide what to name the folders/categories, etc. The overwhelming advantage to me: my system is independent of any library or, more importantly, any OS upgrade. If necessary, I can simply drag/copy the entire folder or part of it to another drive - no loss of anything. No worries about not being supported.

Theoretically you could use Photos in Referenced mode, and store the masters on the NAS but I would not do it. Photos has no tools for properly running in referenced mode, and adding a Network location into that mix is just asking for trouble.

Plus - since Catalina the handling of referenced files is buggy in Photos and the bugs have not been fixed in Photos 6 on Big Sur.

The problem I have is with my external hard drives .Both drives updated to the new big sur photos on my 5K imac but now not backwards compatible with Catalina photos Which means I cannot plug my external drives into my older iMac which is a 2013 model and not updateable to big Sur.

@babowa - can I just ask how you did that? I know it might seem like an odd question, but I always thought that photos had to absolutely always go into the Photos app. If I currently have them in the app and want to move them, do I just export them all there?

If I currently have them in the app and want to move them, do I just export them all there?

File -> Export -> Export unmodified original

You can get images from your Phone and/or camera with Image Capture.

With Photos on High Sierra I kept my Photos Library on a Synology NAS and all worked fine. I had the photos library stored as a sparse image and then would mount the disc image with the library on whatever remote computer from which I wanted to access my photos.

It is now a bit of a shock, having updated recently to Big Sur, to learn that Photos cannot now open this library from the NAS (although it did do me the "service" of "updating" the library.)

Thanks for pointing out the other alternative photo management solutions.

Photos (and it's predecessors iPhoto and Aperture) have never supported having the Library on a NAS. Very few apps do. In fact, only one that I know of - PhotoSupreme. While using the sparse image might circumvent the issues with disk format, the app simply has no ability to safely work over a network connection. That it worked on High Sierra was luck and no more. It was likely to fail at any point.