Duplicate photos - which is the original?
Hello, I'm trying to delete duplicate photos on my Mac, originally taken on my phone.
Some it's clear which is the original, others it's not.
For example, I have two files of the same photo, IMG_0396.JPG and IMG_0371.JPG, indistinguishable in Photos with Get Info
When you export them, you can see IMG_0396 has a later file modified date.
For some reason, IMG_0371 file modified date is different from the file created date. For most of the other duplicate sets usually at least one photo has the same file created date as file modified date.
Next I downloaded an app called Photos Duplicate Cleaner, v1.7, which described additional metadata
I don't know how Photos creates their folder structure, but it looks like 0396 is in an earlier folder than 0371.
Also, what is Editing Software referring to there?
So comparing IMG_0396 to IMG_0371 I would say the original is
By filename: 0371
By file created date: same
By file modified date: 0371
By capture date: same
By stored folder: 0396
By editing software: 0371
The app suggests 0396 as the original and deleting 0371.
It makes sense if it was imported first and created earlier and therefore has an earlier folder, but why the discrepancy with a later filename, a later file modified data, and later editing software version?
Another example of 3 copies is even more complex
So here by
Filename: 0352
File modified: 0563 (the first one)
Folder name: 0352
Looking into it more, I think the File modified date is somewhat meaningless as I may have edited or done something to the file so it's not reflective of its age. I also understand the file metadata is different from the image exif data. Which may mean that the folder name is the most reliable to use. But what about the image number and editing software version?
Photos Duplicate Cleaner will move the duplicate photos into a duplicate album in Photos, and you can delete from there in Photos. Is it safe to let it this third party program alter the Photos Library?
Lastly, I want to move all photos to an external hard drive and have them only reside on the drive and not the main hard disk. Is the best way simply to move the Photos Library?
Thanks all for your help.
MacBook Air, OS X Yosemite (10.10.4)