My Mac has only about 50 MB of free space, while my Photos library uses roughly 115 GB locally and about 1.6 TB in iCloud. I tried copying the library to a 256 GB thumb drive, but it appears to contain only optimized, low-resolution versions; videos and Live Photos do not work correctly. I want to purchase a suitably large external drive—probably at least 2 TB—and move the entire Photos library there in its original quality, while preserving albums, organization, videos, and Live Photos.
I am concerned that disabling Optimize Mac Storage would require downloading the full 1.6 TB library onto my nearly full internal drive first. Is there a way to move the Photos library to an external drive and have Photos download the original files directly there instead? I also need to understand how to safely stop syncing before deleting anything, since deleting synced photos currently removes them from my other devices as well. My Mac is extremely slow, so I would also appreciate advice on freeing enough space to complete the move safely and on choosing a reliable external hard drive or SSD.
3 Answers
Before attempting the transfer, free some working space on the Mac. Check Downloads for old installers, disk images, ZIP files, and large media files; review Storage settings for old phone or tablet backups, unused applications, and unusually large documents; then empty the Trash and restart. macOS needs a reasonable amount of free space for indexing and normal operation, so recovering even several dozen gigabytes should make the process much more reliable. Do not start deleting photos until you have verified that the external library contains the originals and opens correctly.
You probably do not need a premium extreme SSD for this archive. A reputable 2 TB or larger external HDD is generally adequate for storing a Photos library, though it will be slower and more vulnerable to physical damage than an SSD. An SSD is nicer if you browse or edit the library regularly. Whichever type you choose, do not treat it as the only copy—use a second backup drive or another backup method, because a single external drive can fail.
Use a properly sized external drive as the location of your Photos Library rather than copying individual thumbnails or exported files. Quit Photos, move the library package to the external drive, then hold Option while reopening Photos and select the library in its new location. Once Photos is using that library, set it to download the originals instead of optimizing storage. The full-resolution files should then be downloaded into the library on the external drive, so your Mac does not need to hold another 1.6 TB internally. Keep the drive connected whenever you use Photos, and format it with a Mac-compatible filesystem such as APFS if it will be used only with a Mac.
So moving the existing library first does not permanently limit it to the blurry versions? I was worried that I would simply be moving the optimized copies and would still need the internal drive to download the originals.