Take Control of Photos, 4th Edition

Manage the Library

At the heart of Photos in macOS is the concept of the library. (In iOS and iPadOS, there’s only one library—or two if you are using iCloud Shared Photos. See Use iCloud Shared Photos for more.) You can have more than one library on a Mac, but only one can be synced with iCloud.

Here are the details of mixing, matching, and merging libraries in macOS.

Understand the System Photo Library

To simplify the process of syncing files with iCloud, Apple has limited Photos to a single System Photo Library. This is the library that’s capable of syncing to iCloud (see Manage the Library). There can only ever be one at a time (Figure 107).

Figure 107: If you’re not using the System Photo Library, you find no iCloud options whatsoever ...