Binoculars for Sale in Detroit MI
Binoculars are composed, or two telescopes mounted together and aligned to point in the same direction. They allow the viewer to look at distant objects using both eyes. Binoculars are usually designed for specific uses. For this reason, different designs require different optical parameters which are usually listed on the cover plate of the binoculars.
Magnification is one of these parameters, listed as the first number in a binocular description. It represents the ratio between the focal length of the objective and the focal length of the eyepiece; for example, a magnification factor of 7 produces an image that is 7 times larger than the original seen from that distance.
In most binoculars, the amount of magnification is permanent and non-adjustable, though some binoculars have the option to zoom in and out. In most hand-held binoculars the magnification ranges between 7x and 10x.
A larger magnification might require a tripod for image stability, as it’s more susceptible to the effects of shaking hands and surfaces.
The second number in a binocular description is the objective diameter, which represents the diameter of the objective lens. This determines the sharpness of the image. Objective diameter is typically expressed in millimeters.
Binoculars are normally categorized by the magnification x objective diameter.
Field binoculars commonly have a diameter of 35 mm and 50 mm, though smaller ones exist. Astronomical binoculars possess larger diameters, ranging from 70 mm to 150 mm.
Field of View
The third parameter is the field of view. This depends on the optical design of the binoculars, and it’s normally inversely proportional to the magnifying power. The field of view is expressed in linear value, namely, how many feet or meters in width will be seen at 1,000 yards or 1,000 meters.
Binoculars can be used in various circumstances, and many outdoor activities require them.