I am using osX Sierra 10.12.6, and about a year ago, scanned some slides for a friend and for convenience and some quick editing put them temporarily in the "Photos" application, then deleted them.
However today a search with Spotlight reveals that they are still stored (or appear to be) multiple times, typically 5 times such as "picture1.jpg" located in the following paths:
"Masters:2018:02:17:20180217-091606:picture1.jpg" or : "Masters:2018:02:17:20180217-092544:picture1.jpg", etc...
The pictures are not visible in the "Photos" interface, and a search in the "Photos" search engine on file names returns nothing. But the pictures can be opened normally from the Finder where they appear to have all normal attributes.
I have tried to rebuild the "Photos" Library, but this did not change the situation. How to get these files erased forever in a clean way ?