How can I recover lost photos, albums and events when migrating a Photo library to another mac?
I have attempted to migrate a large Photo library (containing prior iPhoto content and Albums and Events) from a 2009 Mac running OSX El Capitan 10.11.1 to a 2013 Mac running OSX Catalina 10.15.7. There was a Photo library running on the 'Catalina Mac'.
I have used Migration assistant and the bulk of the photos have transferred and successfully added to the Photo library already existing on that Mac. However the bulk of the prior iPhoto material has disappeared and the little remaining is scattered throughout the rest of the photos with little metadata and different dates to the original photos. No Album's or Events have transferred.
To re-create the Albums and Event and patch up the missing photos in any manual way will be a huge task.
I would appreciate advice on this problem.
To recreate what I had
iMac 27″, macOS 10.15