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CassBeth welcomes you to our Photography shop featuring 35mm cameras, albums, aps cameras, binoculars, books, cases bags, digital camcorders, digital cameras, drives, film, filters, flashes, frames, really cool guides, instant cameras, lens, memory cards, minox cameras, night vision, nikon, photo software, scrapbooks, slr cameras, telescopes, tripods, underwater cameras, zoom lens, and many other great items. If you can't find it here visit our really great electronics shop.
Binoculars BinocularsRunning the Numbers Binoculars are essentially two telescopes mounted side by side to give a magnified stereoscopic view. As such, purchasing a pair can seem like Physics 101 all over again, but it doesn't have to be. A good pair of binoculars simply offers a bright, clear view that's easy on the eyes and a weight that's light for your load. The difficulty is in determining which factors are most important to you, since choosing quality in one often means diminished quality in the othersor a higher price tag. Running the Numbers Field of ViewThe field of view is the size of the area viewed through the lens. This measurement is given either in terms of linear feet viewed from 1,000 yards or in degrees of field (1 degree of field equals a view -1/2 feet from 1,000 yards). Standard binoculars range from approximately 250 to 600 feet, or roughly 5 to 11 degrees. When manufacturers talk about "flat field," they're referring to a sharp, clear image across the entire field of view. MagnificationBinoculars are usually labeled with a two-number code, such as 7 x 35. The first number in the code represents magnification; so 7 x 35 binoculars magnify images to seven times what would be seen by the naked eye. Most binoculars' magnification powers range from 7 to 10. As magnification increases, field of view generally decreases. ApertureThe determining factor for the amount of light captured in an image, aperture (from the Latin aperire, "to open") is the second number in the two-number code. It represents the size of the object (or front) lens. For example, a pair of binoculars labeled 7 x 35 would have an object lens with a diameter millimeters. Most recreational binoculars range from 20 to 60 millimeters. A large-object lens will increase clarity and is especially ideal for low-light situations. Light Matters MagnificationHigh magnification (factor 9 or 10) generally leads to diminished image brightness. Exit Pupil To determine the exit pupil size of a binocular, divide aperture by magnification. A pair x 35 binoculars would have an exit pupil millimeters. On bright days, the exit pupil size will have little effect on the clarity of your image, but for low-light viewing, you'll want a minimum exit pupil of about 4 millimeters. Antireflection CoatingMost lenses and prisms are coated to decrease reflection and prevent distortion. These are advertised as being coated, fully coated, multicoated, or fully multicoated, the latter offering the best brightness and clarity. Prism Style The highest quality prisms are made with high-density BAK-4 glass, giving optimal clarity and brightness. Focus, Please Design Decisions Exterior Features ConstructionSome binoculars are designed to take a beating while others are quite delicate and must be handled with care. Binoculars constructed from polycarbonate/foam and aluminum are designed to be rugged yet lightweight. Extras for EyeglassesMost binoculars are fitted with rubber cups on the eyepieces to position the pupils at an optimal distance from the lenses. These cups will generally fold down for users who wear glasses. Weighing In The importance of the weight factor depends on your prime uses. Most backpackers will want a small, lightweight pair of binoculars that can easily fit into a pack or pocket. Bird watchers who generally take only day hikes can afford a heavier, bulkier pair1-1/2 to 2 pounds. Portability isn't as much of a consideration for backyard birders or sport spectators who simply want a close-up view of the action. Pricing It Out TLC
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