I got myself a new external HD (non Apple product) which is TM compatible. I primarily got the drive to move movies etc off my iMac as it is running out of space. However, one of the super important things I need is my photos to be backed up. I am aware I can just drag the iPhoto library file to my disk, but i was hoping i could do some clever auto backup - however I'd only want to backup that file with time machine. Any ideas which is the best way forward?