How to Get the Ghost Photo Exorcist Achievement
Ghost Photo Exorcist
Exorcise a ghost photo
You need to take a picture with the Camera, so that it will show a ghost once you look at it in the main menu. Here you have the option to exorcise the ghost from the picture.
Easiest is the one right in the room where you pick up the camera. Go to the door right where you enter this room and look south, then equip the camera and make a picture.