Long ago, somebody posted the location and name of the actual folder that all the photos were in.
They just copied them all into a folder on their desktop, and then dragged the entire thing into an ext HD.
THis saved the photos just like they would be on a camera card, and I would put them all onto a new HD.
Can this be done? Im thinking this way, as iPhoto is going away.
Then I would go thru that process of fixing iPhoto here.
This ought to be obvious, bit it isn't: To make a copy of your photos, don't try to find where they are on the hard drive. Instead, just tret iPhoto like a Finder window. Select all the photos in iPhoto and just drag them to a folder on your external hard drive.