How to force Photos for Mac to Optimise the Storage Immediately

Written for Photos 3 to 5 :

iCloud Photos can help you to save storage on your Mac. if you enable Optimise Mac Storage in the Photos Preferences > iCloud, Photos stores smaller versions of your photos on your Mac when storage space is limited, and keeps the original, full-size photos only in iCloud. Choose this option to conserve space on your Mac. But this option will not immediately take effect. The storage management is fully automatic and will only remove downloaded originals, if storage is needed for other tasks. It will not needlessly remove downloaded photos and videos, to save you from having to download them over and over again. So it will take a while. This may be disappointing, if you want to free large amounts of storage immediately.

You can get everything quickly optimised by starting over with a new, empty library and a fresh download from iCloud. If you are sure, that all photos and videos are already in iCloud, try this:

• Simply make a backup copy of your Photos Library on an external volume, just in case something should go wrong.
• Then delete your Photos Library.photoslibrary from your Pictures folder.
• Now create a new, empty Photos Library. (see: Create additional libraries)

1. If the Photos app  on your Mac is open, choose Photos > Quit Photos.
2. Hold down the Option key and double-click the Photos icon in the Applications folder (or click the Photos icon in the Dock) to open Photos.
3. In the Choose Library dialogue, click Create New.
4. Type a library name and choose a location to store the library.
5. Click OK.

• Make this new library your System Photo Library in the Photos Preferences > General, see System Photo Library overview.

1. In the Photos app  on your Mac, choose Photos > Preferences, then click General.
2. To make the current library the System Photo Library, click Use as System Photo Library.

• then make it the iCloud Photos Library in the Photos > Preferences > iCloud and enable immediately Optimize Storage.

Photos will now download your iCloud Photos to the new library and this new library will initially be very small and only have optimised versions.

There is one drawback: The projects will be missing, because iCloud id not storing the projects. And some named faces may be missing. Photos is storing all named faces in iCloud, but I frequently found that manually added faces circles have not been restored from iCloud. So it is essential to keep an archive copy of your Photos Library, before you let iCloud optimise it. You need a local copy anyway, because it is hard to backup an optimised iCloud Library. A local copy is easier to backup.