Pointing to a new Photo library

Backup drive means it is the external drive used to back up all of my files. I do not use Time Machine. I use Carbon Copy Cloner for backing up the iMac. It preserves the files and structures of the internal hard drive and If I choose to boot from that drive Everything is as it was on the internal drive. Files, folders, position on the desktop, etc. The effect is like sharing the iMac's internal drive on a network except I just unplug the external from the iMac and plug it into the Mini.

When I looked at ownership and privileges it says I can read and write to the external. The option of "Ignore ownership on this volume" It is grayed out.

Sorry for the confusion. By pointing I meant selecting the library on the external drive to use for Photos when I option/clicked on Photos on the mini. (please see the attached image of the external drive's "Pictures" folder). Over the last 20 years and the various Macs I have had stuff appears in the Pictures folder that I did not put there. The iPhotos library was "converted" to a Photos library when Photos appeared in an update of my operating system years ago. So, yes, I do have lots of other stuff in the folder that contains the Photos library. Where and why it is there I don't know.

Hi Tony,

Thanks for taking an interest.

• The drive hooked up to the new mini is a backup drive. Over the years I have learned that, for what ever reason, dealing with pictures and movies on my various Macs has told me "Don't mess with the original files if avoidable". All of my pics are on the iMac and 2 other drives.

• The external/backup drive is Mac OS extended Journaled for compatibility with the 2009 iMac (which has 10.11.4 High Sierra)

• Trying to open an image or print it with the min just gives me a blank page

• Trying to edit the image gives me an error message

• Trying to export an image gives me an error message that the file could not be prepared for export

• I never used iCloud or any other cloud services on my iMac.

• Backups on the iMac are done with Carbon Copy Clone. I have been using it since it came out (long before Time Machine) and it never let me down. It is a bootable clone on my iMac.

After posting my issue on these forums yesterday I had the idea of trying to import an image from to Photos on the mini and a curious thing happened. I got a dialog box telling me that the image I was trying to import was already in the library (that's where I got it from) and it presented me with the two images to compare and see if I wanted to swap! So the computer seems to be able to see the image and present it if only in a very limited form.

I do still have the old Mac. I have been using it while trying to migrate to the Mini (9 days old to me).

There was a time before iPhotos and Photo when I just had images stored on an internal drive. When iPhoto came out I imported all those images into iPhoto. Then Apple went to Photos and the migration from iPhoto to Photos required a conversion but it worked for many years and has not given me any issues. All of my images are in a Photos library which was cloned to an external drive. When I boot from that external drive Photos works as usual. When I hooked that cloned external up to the Mini I pointed Photos to use the library named "Photos Library" on the external it went through a conversion/updating process and left me where I am now.

How else would I migrate the Photos Library on the external to the Mini?

Thanks. I'll give that a try but It means taking the backup drive, plugging it into the iMac and cloning over the top of the backup drive to give me an un=upgraded copy of the Photos library. Or wiping the backup drive and starting over.

Thanks for your help so far Tony. Here is what I have found.

The preferences for the iMac's pictures has the importing function selected as you showed above. This was done when iPhoto was updated to Photos years ago.

My iMac has 2 folders for pictures. One for the old iPhoto and one for the updated Photos. I checked as you suggested the package contents folders of both the iPhoto and Photos folders. The Photos folder shows a correct size in the Masters folder. I did not change anything in either folder. Just checked size.

I did not so any check for the number of files in either folder. Just the size of the folders.

Were you suggesting opening the Masters folder?

Also, I am trying to keep the additional files and folders that are on the iMac and all the modifications to the images as well. Except for the lack of the actual image, this seemed to be no problem with the first pointing at the external drive's Photos folder keeping all the albums, dates, places, etc. But then I notices something curious. Before wiping the external drive and re-cloning the iMac's Pictures contents, I noticed that closing and re-opening the Photos application on the mini lost some of the files and folders that were there when I first pointed to that external drive's Photo's folder. It's like some connections are being lost to the external.

I think you may have hit the answer. When I tried to do the ignore permissions I must not have done it correctly because now when I select the Photos library on the external the progress bar on the "updating library" is going MUCH slower.

I will let you know how it goes. It is just churning away but the last time I tried doing this it finished in a few minutes.

That was it Tony! All the images on the external are visible and my existing folder structures are intact. Thanks for your help.