deleting photos

To move your Photos Library to an external volume, as recommended by Rich, see this support document: Move your Photos library to save space on your Mac - Apple Support

It is essential to use a n external drive with a compatible file system format, or you will have permission errors and other problems.

You will not want to have to bother with an external drive at all times. That would defeat the purpose of a portable Mac. I am using a small library with just my favorite photos on my Mac Book pro and a large archive library on an external drive. That is working out rather well.

If you want to move the library off your system drive, get a pair of external drives, not just one drive. You will need one drive for the external library and one drive for the backup copy of the drive with your photos library.

You would need to delete a lot of photos to free up significant space. Another option would be to move your Photos library to an external drive formatted Mac OS Extended (Journaled).

-- Rich

1. IOpen Photos and click Photos in the menu bar (top left corner)
2. Click Preferences…
3. Make sure the iCloud tab is selected
4. Click Optimize Mac Storage if iCloud Photo Library is already turned on

If you really want to delete them (that means they won't be anywhere any longer), you can just delete them within your Photos app.