Hi all, I have a 2009 iMac at the moment. I have just replaced it with a 2012 Mac Mini i7 fully specced up with fusion drive. I have also purchased a Dell Ultrasharp U2713HM as my monitor as I wanted the non reflective coating for photo editing. Im connecting this with a Mini display port to display port. My question is, Would I be able to use the iMacs screen as a second screen somehow to run with the Dell? Many thanks, James.