How can I change the default directory for iPhoto?
iPhoto has a default directory (~/Pictures/iPhoto Library) that can be changed in a fashion similar to the way iTunes change the location of its music library.
What you need to do is to Hold ‘Option’ as you start up iPhoto from your Dock or /Applications.
You will then see the above screen, click on “Create Library” to create a new iPhoto library, and “Choose Library” to use an existing one.
To create a new library, just click on “Create Library” and enter the name of your new iPhoto library (Eg. Aloy’s iPhoto Library). You can also select the directory to save the iPhoto Library in.