This scan mode lets you compare folders against each other and is particularly useful when you need to compare images on a backup drive with the ones on your computer or merge two different folders. The Folder Comparison mode allows you to select source folders, images in which will be considered originals, and target folders, images in which will be considered copies if any duplicates are found.
To scan your image folders using this mode, select Folder Comparison from the Scan Mode drop-down menu. Then add some source folders to the area on the left and some target folders to the area on the right.
When you’re ready, press the Start Scan button to begin the scan.
When the scan is finished, Duplicate Photo Cleaner will display a summary. Click on the Go Fix Them button to go to the scan results. Images in the Source Folders will be marked as master images with a red “M” icon.
Master images are treated as originals, so you won’t be able to delete them unless you disable master image protection (a pop-up will appear if you try to delete a master image and you’ll be able to disable master protection from the pop-up).
You can delete duplicate files from Target Folders just like you normally would.