Photo Snipe 

The act of sneaking up behind an otherwise very nice/cute/awesome photo, pulling a face and getting away undetected.

Prima: "Dude, I would have got an awesome picture of two chicks making out on the dancefloor, but some douche totally photo sniped it!'
Secunda: "Ah, the photo sniper: moves like a fox, acts like an idiot."

Photo Snipe by Amrom February 18, 2009

Photosniped 

When one is photographed unbeknownst to his or her own awareness and have not been made aware by the photographer until immediately after the photo has been taken, a long period of time after the photograph has been taken, or in extreme circumstances, notified by the emergence of a picture in a public forum or social network.

Billy thought nobody noticed his terrible drunken attempt at his version of the lawnmower dance, until he logged onto his Facebook account the next day to discover he had been photosniped, and live action pictures of his terrible dance were all over the social network.

Photosniped by JohnnyAppleweed February 22, 2013

Sniper Photos 

SNIPER PHOTO; A photograph taken of a subject to be used against them from so far away, the subject has no idea they are being photographed in a compromising situation.

Kate Middleton nude sniper photos were published in the scandal sheets.

Sniper Photos by theaccusersgift September 30, 2012