I turned on Photo stream for a minute on my Macbook Air and remembered right away why I had it turned off previously.. it duplicates the photos stored in Photo Stream because PS does not support the .HEIC format .. so now I have 1,000 photos duplicated as there is a .JPG version from PS and my original version which ends in .HEIC. For those that have made this mistake as well, how do we delete all the duplicates quickly?