Jul 12, 2017 How to Move Your Apple Photos Library to Another Location Matt Klein @howtogeek Updated July 12, 2017, 11:14am EDT Apple’s new Photos application was released as part of a. Mar 03, 2019 What’s Missing in iCloud Photos Family Sharing. While Apple does allow you to create shared albums in iCloud Photos, it doesn’t allow a way for families to create a single library for all of.
Photos for Mac has two modes of importing photos, managed (the default) and referenced. This is determined by the Photos > Preference > General > Importing. If you disable 'Copy items into the Photos Library', Photos will not store copies in its library but reference the photos in their original location. That can help to save storage by keeping the original photos on an external drive. See this Help page: https://help.apple.com/photos/mac/1.0/?lang=en#/pht12e7a8015
Aperture users migrating to Photos might be tempted to set up a referenced Library in Photos, since referenced libraries worked well in Aperture.
Unfortunately, the support for referenced photos is still poor in Photos. It is a little better than in iPhoto, but still cannot be recommended in Photos for several reasons:
Therefore, risking a referenced library will mean a lot of work for reestablishing the connection between originals and the versions in the Photo Library, if you ever need to move the library, or need to replace the drive, or restore the library from a backup, and sooner ar later this will be necessary, since any drive will fail sooner or later.
And you have to manage the originals on your own. This should only be done by experienced users, not beginners just starting to use Photos. It is easy to make mistakes and accidentally delete the precious originals.
Occasionally the thumbnails in the Browser may not correspond to the enlarged image, or the thumbnails may appear to be corrupted, but the enlarged image is fine. While iPhoto and Aperture have a tool to recreate the thumbnails, such a tool is missing in all versions of Photos from Photos 1.0 to Photos 4.0.
We can use this simple workaround to fix the thumbnails: To rebuild the thumbnails edit them slightly, so Photos will be forced to render new thumbnails. This is best done by rotating the photos back and forth, because rotating by 90° degrees is non-destructive and can be applied to multiple photos at once without having to open the Edit window for each photo individually.
This may not suffice, if your photos are RAW photos and the corrupted thumbnails are caused by a difference in RAW processing. In that case try to reprocess the RAW files:
Before applying this fix I'd repair the Photos library, just in case there are other hidden corruptions. Only, if your library is an iCloud Photo Library wait with repairing as the last resort. Repairing will result in uploading the complete library again and comparing the photos to iCloud. You may not want to have that happen on a slow Wi-Fi.
To repair the Photos Library:
This may take a while for a large library.
Update: There is now an Apple Support Document describing this fix: Fix missing or incorrect thumbnails in Photos - Apple Supporthttps://support.apple.com/en-us/HT205069
Update 2: The link above does currently not work. The document has been removed for all language versions.