How to access old photos from Time Machine backup?

You have to use Time Machine to access the Time Machine backup from the old computer.

The backup of a Photos Library needs to be restored by running Time Machine, or the internal links may not be restored correctly.

By default, Time Machine will only browse your current backup volume, but when you hold down the (opt)key when launching Time Machine from the Time Machine menulette in the main menu bar, you should be seeing an option "Browse other backups". Then you can select the older Time Machine drive to restore from.

You would have to restore the Photos Library from the old Time Machine backup to a folder on some other drive. Photos cannot open Photos Libraries that are on Time Machine volumes, because of file ownership conflicts.

You can access the backup from any computer, if you can mount the Time Machine volume on your new computer. Or do you not have a suitable cable? Just use the "Browse other backups" option to open the old backup on your new computer.

So you were able to restore the Photos library successfully from the Time Machine backup disk to a work area, but were unable to open the library from the work area afterwards?

Do you know how old the system version on the old computer was? What is the system on the computer you are using to try to open it? (A high degree of version mismatch when opening an older library is tolerated, but Photos cannot open a library from a higher version of Photos.)

jshire wrote:

Thanks. Perhaps I'm not being clear. When I do that it will not open Photos library. It says 'Cannot open this version of Photos Library.'.

Even when you select the library in Time Machine and restore it?f

What system are you currently running and under what system was the library created?

But you have to restore its to verify its content. There's no other way. You can restore it and keep both the restored and original libraries. Then when you've confirmed what's in the restored library you can delete it.

Hold down the Option key when you access the Time Machine menu and select "Browse Other Backup Discs…". You should be able to browse that TM drive.

Your photos are in the Photos library, not the Photos app. You want to enter Time Machine via its menu in the Menu bar, locate the library and hit the Restore button.