ok here goes, i want to upgrade to 10.9.4 and i want to do a clean install so i am backing up all data to usb drive. I am fine till i come to my iPhoto picture files data and there lies the issue. I just copied a folder from my macbook to usb that was well over 50gb and it went in about 10 mins, now I want to copy a 7gb iPhoto and it says 6 hrs wow what the difference can some one tell me.