Binoculars Features Comparison
The key feature in a pair of binoculars, the magnification, is the first number before the "x" and included in the name, but other features are also important. Budget binoculars tend to be compact and lightweight, two attributes that make it easy to carry them in a pocket, purse, backpack, or suitcase or hold them up for long periods (consider a tripod for heavier binoculars). The field of view determines how much area you see when you're 1,000 yards away -– a larger field of view can help you see movement in a wooded area or catch all the action on a football field. Eye relief is the distance between your eye and the lens where the image will come into focus. Because glasses add distance between your eye and the lens, this feature is particularly important if you wear specs. Dioptric focus lets you adjust each eyepiece separately so you can compensate for the stronger or weaker eye. In between the lenses and eye pieces of the binoculars is a prism that turns the image right side up. Binoculars with Porro prisms have lenses and eye pieces that are slightly offset; roof prisms line up the eyepieces and lenses, making the whole more compact and slim.
|Weight||Field of View||Eye Relief||Diopter Adjustments||Prism|
|Bushnell Permafocus 7x35 estimated price $44||22.5 oz (fits tripod)||578 ft||12 mm||No||Porro BK-7|
|Olympus Roamer 8x21 estimated price $30||6 oz||336 ft||11 mm||Yes +/- 2||Porro BK-7|
|Bushnell Powerview 8x21 estimated price $14||7 oz||378 ft||10 mm||No||Roof BK-7|