Why won't photos from external drive stay on my computer (iPhoto) once I disconnect the external drive?
I'm trying to move photos from my external drive to my new computer. When I connect the external drive, I'm able to view all the photos in iPhoto, and I'm able to drag photos to a desktop folder and/or directly into iPhoto. But, when I disconnect the external drive, I no longer have access to the photos on my computer. I'm sure there's a step I may be overlooking but I'm using the same process I've used in the past and cannot determine next steps.
MacBook Air (13-inch, Mid 2012), OS X Mountain Lion (10.8)