Our face detection features are good, but not perfect. Sometimes we'll miss people in the shadows of a photo or where the resolution on the image just isn't good enough to give us confidence in the match. You might recognize them yourself, however. Here's how to add them to albums manually.
Use the selection tool at right to draw a box around their face (usually by clicking in the upper left of the face and dragging diagonally down to the bottom right.) A comment box will appear at the bottom right of the window. If you just want to make a quick comment like "I think this is Bobby Jones" that's fine. You can always update it later.
Currently, this won't automatically pull up Bobby Jones from the Gallery. However, you can get tricky and manually add Gallery views for detected faces. Just go to another picture in which Bobby Jones appeared or find their face in the gallery. Copy the link. Go back to the face selection where that person appeared in the shadows, and paste the selection. Press post. If you previously entered the simple "I think this is Bobby Jones" or similar comment, you can delete that now. Click outside the sidebar in the picture itself, and mouseover that new selection.
The person's face should now appear just as if they'd been automatically detected. If you want them to appear in Bobby Jones' album you'll need to drag the picture from the All Pictures view into the album with his name on it. Any changes to the Bobby Jones Gallery view (such as a change in his Gallery picture) will be reflected even though he was manually added.
Feel free to reach out if you have any questions. You're obviously a rock star if you're already asking questions like this.
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