What Is Short Light?
Short light is type of studio lighting setup, where the face side which is further from the camera gets the main light. see the diagram for details. In this type of lighting setup, the side of the face which is toward the camera gets less light then the side facing away form the camera. The effect you get when using this lighting setup is a thin face, this is why it is good to photograph fat (or chubby) people with a short light setup.