I keep photos stored in an external hard drive attached to a Mac Mini. The Mac Mini is shared by my family. We each save our own photos in separate folders in the external hard drive. In iPhoto, Preferences, Advanced, Importing: "Copy items to the iPhoto Library" is unchecked. When I "Reveal in Finder" any photo in iPhoto, it opens a Finder window to where the photo is stored in the external hard drive. Would I be able keep photos stored in the external drive with the Photos app? Would I be able to keep photos in separate folders on the external drive (i.e. not copy items into the Photos Library) and just "reference" the location like I am able to in iPhoto?