You can open photos in iPhoto but side-by-side comparisons are not easy.
You can open a Mac graphic app and compare two photos or more, but sometimes the details in a photo appear exactly the same to the naked eye. A true visual comparison of multiple photos starts with an app that does that. It finds not only duplicates but images that are similar. That’s what Unik does (as in, unique) and it does so about as simply and elegantly as possible.
Drag and drop a folder of photos onto Unik. That starts the photo comparison process. All the photos are added to what looks like a modern day version of a contact sheet.
Unik gives you options to edit batches of photos, and even finds and compares photos that have been cropped, flipped, rotated, or gray scaled from the original.
Each batch of photos can have different similarity thresholds which are fully adjustable.
There’s even a built-in option to select images from a group based on date, size, resolution.
Unik is a good value if all you’re trying to do is detect duplicates or similar photos in a folder. While it can do bulk editing, there are other Mac apps which do a better job of batching edits.
And, it’s important to backup your photos and use only copies when using Unik to find duplicates or similar photos. Unik can integrate with iPhoto, but it’s better to use copies.