Duplicate Photos on iMac

Hi

If this is a smart album in finder, then it is not showing any files from the photos app. (Check by clicking on these images and at the bottom of the pane it will tell you where the file is)

So if ALL your images are in the photos app, you can safely delete the images found by finder, but...

how do you know the ones you are deleting are in photos. How have these images got into the folders they are in. As part of your duplicate removal process, you really need to understand where these files have come from, and checking they exist in photos before deleting them.

It depends on how you are transferring from your phone.

For example - if you used the image capture app, that would put them into a folder for you to import into photos manually. So how have the HEIC/HEIF files found their way to a folder?

Have you exported them from photos using the file>export unmodified original. Have they been sent to you by someone else (in an email for example) or have you transferred them directly from your phone using image capture or other app?

The only HEIF images I have in folders on my mac are those I copied (using image capture) from my wife's phone as a backup.

You are going to need to explain your problem with a little more detail.