How to make a local backup of your iCloud Photos synced library

iCloud Photos is a great way to have all your images and videos across all your iCloud-linked devices. Apple lets you select an optimized option for storage, which ensures the full-resolution of your media is uploaded to iCloud and retained there (and accessible via icloud.com) while each end point, like an iPhone or Mac, has just a set of vastly reduced thumbnails. When you want to work with or view the full-sized photo or movie, double clicking or tapping retrieves it. You can have your cake (preserve storage on devices) and eat it too (have a huge Photos library).

The fly in that ointment is that with optimized image storage set on all your devices, you cannot make a local backup of all your media, as I explain in a 2017 column. I offered one full download strategy in 2018 for a reader who wanted to move from iCloud Photos to another service. Neither of these help with ongoing backups.

Reader Todd wrote in recently with a question and suggestion that’s brilliant. He pondered a solution:

1. Create a second account on a Mac intended just for iCloud Photos backup and log into that account.
2. Via the iCloud (Mojave and earlier) or Apple ID (Catalina) preference pane, log in to the same iCloud account used for iCloud Photos.
3. Connect an external drive and use Photos to create its library there.
4. Launch Photos and configure it to perform full-resolution downloads in Photos > Preferences > iCloud.
5. Wait until the initial synchronization is finished, so all the images are downloaded.
6. Log out of the second macOS account and back into the primary one.
7. Eject the external drive.

The next time you want to back up your Photos library, you log back in to that second account with the drive attached, launch Photos, and it should update just as you expect.

This strategy checks all the boxes. It lets you keep an optimized library on your Mac, having sync via iCloud Photos, and create a full, local backup as an extra guard against anything happening to Apple’s redundantly backed-up servers or your account.

This Mac 911 article is in response to a question submitted by Macworld reader Todd.

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