User blog comment:Heatedpete/Battlefield 3 Beta Experience - no. 1/@comment-5524047-20110930114959/@comment-5524047-20110930121130

After the second duo of M-COM stations, up the escalators, on the right hand side of the corridor is a photo booth that you can go inside. A hot-tip that says "Press B to Interact" appears. Doing so whilst inside and sets the bulb off. Aside from that it seems to have purpose at all.