This project analyzes the class of imaging systems that defy the single viewpoint (SVP) assumption. They are made of a standard perspective camera looking into a refractive medium through a flat interface. The refractive medium is most commonly water. The two cases are either that of aquaria, where the water is enclosed in an air-based environment that the camera is in or where an air chamber containing a camera is enclosed in a water-based environment. Both of these cases have the same imaging model.