@mikemyers I am a Windows 10 user not a Mac user but I believe both versions use an SQLite database and I have written at great length (sorry big posts appear to be a habit of mine) about the issues of the wrong DOP meeting the right (or wrong) database entry Unwanted virtual copies - #86 by BHAYT.
If a database is oblivious to a particular Photo in a particular directory/folder it will absorb/ingest/import the DOP automatically based upon the ‘Preferences’ for handling sidecars (DOPs) or when manually directed to ‘Import’ the sidecar (if you manually import you will always wind up with a Virtual Copy - the photo before the import counts as the [M]aster and the import becomes copy [1]). If it has never seen that photo before then all should be O.K…
If the database has “seen” that photo before, i.e there is a database entry for that exact photo in that exact directory (currently PL does not check and start matching up the same photo filename regardless of the directory as some other products do! at least on a PC) then a check swings into place that will determine the fate of the attached DOP, but PL5 will protect the sanctity of both the database entry and the incoming DOP at all costs.
The field is the Uuid just behind ‘ShouldProcess’ as shown below
there will be a similar Uuid for all copies held in the DOP. I haven’t run a test were one of the photos [M] or [VC] matches the database and the other(s) doesn’t (don’t) but certainly a mismatch between the [M] Uuid and the database is going to start the creation of Virtual Copies!
So the only way to import successfully, regardless of what media you use or whether you access the original photo across a LAN (I have done that with some success but only by dividing the exports between two systems and then …) once a Uuid is allocated that will not/does not match the system you are going to import it into there will be Virtual Copies; you can escape this fate by ensuring that there is no corresponding entry in the database you are importing into, i.e. by throwing away the database so there won’t be a problem!!!
If you doubt the above the test is simple;
- Edit a photo in PL5
- Open the DOP in a text editor and change the last digit in the Uuid I identified above, i.e. in my example change the 3 to a 0 and then save the DOP file.
- In my tests PL5 has picked up the change instantly and I have a shining new Virtual Copy to play with (whether I wanted one of not)!!
I have “moaned” about the fact that the VCs cannot be promoted to [M] status etc., there is much that DxO could do to help manage the fall-out from this situation but that is in the future perhaps. Things might be simpler of more complex on a Mac but the above comes from many tests that I have run on a PC.