What is the difference between the Roof Prism System and Porro Prism System?
In roof prism binoculars, the prisms overlap closely, allowing the objective lenses to line up directly with the eyepiece. The result is a slim, streamlined shape in which the lenses and prisms are in a straight line. Roof prism binoculars are less bulky and more rugged than an equivalent porror model. In porro prism binoculars, the objective or front lens is offset from the eyepiece. Porro prism binoculars provide a greater depth perception and generally offer a wider field-of-view. Because of the simplicity of this system, some of the best values can be with a porro design.
