I received an online message that my disc space is almost full so I need to eliminate some files. I found a folder titled migrated photo library, which I think I don't really want, but it happened by accident. I want to find out first what this is before I delete it. Can anyone tell me what a migrated photo library is?
MacBook Pro (Retina, 13-inch,Early 2015), OS X El Capitan (10.11.6)
This document explains, how the disk space is shared by your current Photos Library and the original, migrated iPhoto Library or Aperture Library: Photos saves disk space by sharing images with your iPhoto or Aperture libraries - Apple Support
The ".migrated" library is exactly your old iPhoto Library or the Aperture Library. Only the filename extension has been changed. I would copy this library to an external drive to keep a backup of the original files and the items, that could not be migrated to photos, like your projects or album descriptions or smart albums, and then delete it from the system drive. the problem is, that both libraries are sharing the same image files. While the image files are still in use in the old, migrated library, deleting the same photos from your new Photos library will not free any storage, because the old library is still needing the files. SO removing the library to a different drive will definitely help.
This document explains, how the disk space is shared by your current Photos Library and the original, migrated iPhoto Library or Aperture Library: Photos saves disk space by sharing images with your iPhoto or Aperture libraries - Apple Support
The ".migrated" library is exactly your old iPhoto Library or the Aperture Library. Only the filename extension has been changed. I would copy this library to an external drive to keep a backup of the original files and the items, that could not be migrated to photos, like your projects or album descriptions or smart albums, and then delete it from the system drive. the problem is, that both libraries are sharing the same image files. While the image files are still in use in the old, migrated library, deleting the same photos from your new Photos library will not free any storage, because the old library is still needing the files. SO removing the library to a different drive will definitely help.
Wwhen you switched from iPhoto to Photos app, the old iPhoto Library was "migrated" to the new Photos Library and the old was was renamed by upending .migrated to its name.
If all your images and videos migrated successfully to Photos, you can delete this iPhoto Library. Be aware, however, that you will regain very little space. That's because both libraries reference tohe same files on your drive.
To find our what takes up the most space, look into About This Mac in the Apple menu.
What is a migrated photo library?
