What kind of selfie gets the best match results?

A clear, front-facing photo of the person's face, taken in reasonable light — the kind of thing you'd use for a profile picture. Tell guests to skip sunglasses, heavy filters and dramatic angles. And crucially: no HEIC/HEIF files, so iPhone users may need to send a JPEG version. The selfie is used purely to find that person's matching photos and isn't shared with anyone else. If you're worried about older relatives struggling with this, a quick note in your guest instructions goes a long way.