After updating to 10.10.3 and launching photos app for the first time, i clicked on the option to enable iCloud sync (download originals to this machine) and now my disk space has gone down by a few gigs. I remember with iPhoto, i also enabled iCloud sync and so i had copies of pictures on my local drive. Is it possible that I now have duplicate copies of pictures one for iPhoto and one for the new photos app? If so what's the "safest" way to delete the dupes (without any negative impact)?