My Mac is SO SLOW again and I'm betting it is because of the pictures. I dont think the deletion of duplicates task was successfully completed. Can you remind me how to do that again? And then move them onto the external hard drive?

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Yea, it's a little complicated to go through via email.  It may be a matter of your iphoto library having almost outgrown your internal drive.  iPhoto can detect a library housed on an external drive but the issue is to have a separate drive connected and also have that one backing up as well.  Your current backup may be large enough to encompass both your internal drive and the external you would add if it is a 1terabyte or larger drive.  That's only one possibility.  But we do need to get those duplicates effectively dealt with first.  You should have a copy of Duplicate Annihilator on your computer already that you can run however you can also download the latest version of Duplicate Annihilator from here:  
Brattoo Propaganda Software - Products

Pretty simple to use.