Logically, their prices are correspondingly high. Ergonomics or adaptability of the prismatic handling, grip and face is a primary factor to be considered. Whether we opt for economic as for binoculars of high cost models, is convenient to weigh them carefully, checking for ease of grip and handling (distance to ring approach, etc.) as well as its ease of vision (attention to the adaptability to the eye sockets and the vision with glasses). The quality of the lenses is essential in a prismatic optical performance. Input, should be discarded immediately binoculars with so-called lenses organic, which means simply that they are manufactured with plastics or similar products, because long term its optical performance tends to decrease noticeably (although they cheaper binoculars and reduce its weight).
Mineral lenses are, consequently, first sign of quality of a binocular, and the different treatments and precision of design applied by the manufacturer sharply increase its performance. In general, for some quality binoculars should require multitratadas lenses and/or aspherical, manufacturing processes that improve the quality of the lens and translates into a greater sharpness, brightness and colour transmission. Some modern models of binoculars for astronomical use use including fluorite, material that minimizes the optical distortions and lenses the image color. The prisms are a species of mineral lenses of prismatic shape that transmit and divert the light in the interior of the prismatic. As we have commented for the lenses, the quality of the prisms is proportional to the quality of image. Of course, organic prisms must be rejected, and between minerals are of special quality which have undergone treatments, generally called bak-4? or covered. Mode of arrangement of prisms identifies two types of binoculars. In the classic model, the prisms are arranged in two separate chambers and are not aligned with respect to the mount, calling in porro prisms (sounds bad, but so called).