I have purchased an external Hard drive to move my grandfather's iPhoto library from his iMac's internal to it (so that it can be accessed by both of my grandparent's accounts instead of just one since they share the same camera), and was wondering if moving it to the external would be enough of a back up or if it should be backed up again? the drive will be partitioned so that there is 400gb available for time machine and 100gb available for "everything else", like the iPhoto library for example. I partitioned it so that time machine backups don't squeeze the iPhoto library space down to 0. Is it nonsensical to have the library back up to the other partition as well since it is on the same drive, or would that in fact be a good idea? I don't know so that's why I'm asking Thanks!