Astronomical Binoculars

About

Any binocular can be used for an occasional casual peek at the sky. However, binoculars with large light-gathering objectives (50mm and larger) are better suited for more serious astronomical observing than the compact or smaller general-purpose binoculars you'll usually use at football games or on vacations. A list of the large-aperture astronomical binoculars that we carry that are best suited to astronomy, arranged by manufacturer, follows this introductory material. There is nothing like viewing celestial objects through a large aperture binocular. Using a 100mm binocular is like using two 4" telescopes, one for each eye. The binocular view is more expansive, though, much wider than your view through a telescope. Large objects, such as the 3.5° wide Andromeda Galaxy, will fit in the field of many astronomical binoculars. Through a telescope, only a portion of these objects will be visible at a time, making it difficult to visualize their true overall shape. Through large-aperture astronomical binoculars, you see nebulas, globular clusters, comets, and galaxies in their entirety, floating in deep space and set off against a background of star-spangled darkness. Another advantage to binocular astronomy is clarity. By using both eyes simultaneously to observe, you see up to 40 percent more detail than you do when using only one eye as you do when squinting with one eye through a telescope eyepiece. Your brain normally combines the views seen through your two eyes into one image, instinctively using only the sharpest portions of each eye's view to build up a single sharp image. You can probably see this effect for yourself. Try looking at small printing on a sign or eye chart some distance away, covering one eye with your hand. Then take your hand away and look with both eyes. The chances are good that the printing seen with two eyes will be more easily readable (sharper, and with higher contrast) than the printing seen with either eye alone. This is the effect that