Hello Léonie,
Thank you for the explanation about Hidden People album. makes sense.
The album isn't hidden.
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Using "Review more photos" (This didn't work earlier for some reason, for all People, now it works again)
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I did the yes/no thing for a while... (only had to say 'no' because none of the photos offered had Linas in them)
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Unfortunately, this didn't do the trick.
Photos must have detected the face somewhere on those photos but doesn't show where.
For example:
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Two faces detected. The one on the left is correct. The second is still the same "ghost" (name: Linas)
If I select the first (left) face, the system shows me the face on the photo with a circle. If I select Linas (right), no circle. Linas is the ghost.
Now. I could locate manually the 7 pictures with this "ghost" in it using the People album corresponding to the person "Linas", and hit "This is not Linas". Now the smart album previously created shows 6 pictures instead of seven, as expected.
I'll do it only for one; I'd like to keep the others as examples. I want to find the reason for this.
However, this is a particular case where it's easy to determine the list of ghosts using a smart album (because Linas is shown on pictures taken when he wan't born yet). But impossible to know if there are more ghosts elsewhere in the database...
I would be grateful if I could find all such ghosts in the database.
I noticed this problem by pure accident. Maybe I'm not the only one to have the problem. Maybe it is a bug or a database issue.