Merging Photos Libraries

That is right, Yer_Man. We can now import items directly from other libraries. But merging by importing another library it is very limited.

• We can only import items from small libraries - whenever I tried to import from a library with 50000 items or so , Photos crashed during the preparing stage, with a message about running out of application memory. Importing small libraries is fine, as long as they are not the iCloud Photos Library.
• And importing from another library will only import the media (photos, videos), but without the keywords or named faces. And the structure is also not imported. The albums and folders will be missing.

• Merging in iCloud will merge the libraries including the structure - the albums and the folders will be merged, including the keywords and many of the named faces. Only the projects will be missing.

If our photos are already in iCloud anyway, it is a useful method, to merge large libraries including the structure. But it is slow and requires a lot of patience.

To Jim's question:

"It sounds like my original iCloud Photos library will be disabled. Or at least some part of it. And any Shared Albums. Furthermore, it sounds like the second library will become a [replacement] of the System Photo Library.

I am concerned about proceeding."

Jim, the problem is, that you can only have one System Photos Library at a time, and only the System Photos Library can be enabled for iCloud Photos.

As a precaution:

• Make backup copies of both your libraries that you want to merge, before you proceed.
• Make safety copies of the photos in your Shared album, that are not already in your library.
• Your Photos and the Shared albums will come back from iCloud, once you have merged the libraries, but only the Shared albums, that are still in iCloud. If the owner stopped sharing them, it is better to save the photos you want to keep, before switching iCloud to a different System Photos Library.

To merge the libraries:

• Move the second Photos Library, the one you want to merge into your iCloud Photos Library, to the folder, where you want your System Photos Library to be. This second library will become the new System Photos Library. The library needs to be in a location, that meets all requirements described here: Move your Photos library to save space on your Mac - Apple Support
• Now make the second library your system Photos Library and turn on iCloud Photos and your shared albums. And wait.

If you already own Power Photos, you can open both libraries at the same time in Power Photos and directly drag albums or folders between your two libraries and Power Photos will merge the items, even if one of the libraries is your iCloud Photos Library. This is what I am now using on Sonoma. it saves me from having to switch between System Photo Libraries.

Power Photos will not change your selection of the System Photos Library. If you merge another library into your System Photos Library, the library will remain your System Photos Library.

The most recent version of PowerPhotos is supporting iCloud Photos.

See: https://www.fatcatsoftware.com/powerphotos/VersionedDocs/v7/icloud_photo_library.html

You can even merge an optimised iCloud Photos Library with another library using PowerPhotos.It may be somewhat slow, if many photos are needing the download from iCloud. But Photos for Mac cannot yet import from an iCloud Photos Library at all.

You don't need to use iCloud with version 9. You can simply import from one library to the other.

Importing one library into another with Photos you'll lose any albums you've created in your organizational efforts. However, the paid version of PowerPhotos import albums. The following is a comparison of the importing capability of Photos vs Power Photos.

PowerPhotos:           Photos:

Albums***                                           -----------

Smart Albums (as regular albums)** -----------

Captions                                             Captions

Titles                                                   Titles

Keywords* Keywords (some but not all in tests)

Original images                                  Original images

Edited images                                     Edited images

---------------                                        Locations

Favorites                                             Favorites

Can detect and exclude                      Duplicates

duplicates upon import or not

Neither method could import/merge projects. 

Both methods could import older iPhoto libraries into a Photos library when the iPhoto library couldn't be migrated into a Photos library. 

*The Photos app only imported 84 keywords our of 97. PowerPhotos merged 147 keywords, some which apparently were in the images but not read by Photos at the time of import or keywords delete along with photos but not purged from the database.

**The original library had 90 Smart Albums. All were merged by PowerPhotos but, as indicated above, the Smart albums were brought over as regular albums. No album of any kind were imported by Photos.

The original library had 34 regular albums and 1 folder with some nested albums. PowerPhotos merger all of them successfully.

The original library had 72 videos. Photos imported only 57. PowerPhoto got all 72 in its merge.`

I am not sure, how it is supposed to work now - which of the Support documents is correct. Currently I prefer to use Power Photos to import items from one library into another.

OT, with regard to the merging of keywords:

"Keywords* Keywords (some but not all in tests)"

It seems, like keywords embedded in the originals will be transferred when importing, but not the new keywords assigned with Photos to the versions.

the Help pages are inconsistent - the user guide does notsay that keywords are not imported, and also this does no longer say, that duplicates will be imported:

• Sonoma version: Import photos from another library in Photos on Mac – Apple Support (UK)
• Monterey version: Import photos from another library in Photos on Mac – Apple Support (UK)

But the separate KB article still say that keywords are not imported, hidden away in the footnote: Import photos from another library in Photos on Mac - Apple Support

using Mac Photos only on my computer -Sonoma 14.3.1. NOT iCLOUD

I am getting more confused. what are the correct steps as in number 1.....number 2.....etc

all I want to do is to merge 2 libraries without loosing any photos.

I discovered I have 2 libraries with the system Library being a small one. without deleting any photos . I tried reading and implementing what apple says to do , it gets scary. how does "import" from one library to the other work? any clarification and especially steps would be appreciated.

I'll change the user tip to reflect the keyword issue. Thanks

If I buy Power Photos and use it to merge 2 libraries into one, will iCloud consider that library the System Library?

I have a 2023 Mac Studio 1 with latest version of Sonoma 14.3.1

I'm not sure PowerPhotos will work with an iCloud Library, particularly one with Optimize Mac Storage enabled. I don't use iCloud so haven't been able to confirm or deny.

If you merge two libraries into one and set it as the System Photo Library iCloud will recognize it as such.