I have a 2011 13" MBP with a 320GB SATA drive. Recently I've been getting messages stating I'm running out of HD space. I can't install the latest software update due to this problem. I have 3.5GB free out of the 320GB total. I'm no expert but it appears most of my HD space is taken up by the 19,000 photos in iPhoto(171GB) (see snapshot). The movies (80GB) must be videos in my iPhoto library as I don't have any movies on the machine. My plan to free up space is to backup my HD using Time Machine to a external HD (Seagate Free Agent) and then delete a lot of the photos and videos from my iPhoto library. Am I looking at things correctly and does this make the most sense to solve my HD storage option??? Thank you in advance.