Celestron SkyMaster Pro ED 20 x 80mm Binoculars are the ideal choice for amateur astronomers or anyone who observes at great distances. The SkyMaster Pro ED uses superior optics, coatings, internal parts, and housing materials. With large objective lenses, BaK-4 prisms, ED glass, and fully multi-coated optics utilizing Celestron\u2019s proprietary XLT coating technology, the view through a SkyMaster Pro ED sets the standard for astronomy binoculars.ED Objective LensesExtra-Low Dispersion (ED) glass virtually eliminates chromatic aberration, also known as color fringing, a visual phenomenon common in magnified optical systems. SkyMaster Pro ED delivers edge-to-edge sharpness, excellent color correction, and razor-sharp images. Not all ED glass is created equal. Celestron\u2019s high-quality ED glass delivers brighter, sharper images than non-ED binoculars. The difference is especially apparent in low-light conditions. Celestron\u2019s legendary SkyMaster binoculars get an upgrade with ED objective lenses for superior images virtually free of chromatic aberration with lifelike color, increased resolution, and improved contrast.Coatings and PrismsAll of Celestron SkyMaster Pro ED\u2019s lens surfaces are fully multi-coated and feature Celestron\u2019s proprietary XLT optical coating technology. These powerful coatings, similar to the ones you\u2019ll find on our observatory-grade telescopes, decrease reflectivity for higher optical throughput across a broad range of the visible light spectrum. What\u2019s more, the prisms inside the binoculars are made of high-quality BaK-4 glass, further boosting light transmission. Working together, the fully multi-coated lenses and BaK-4 prisms deliver more light from your target to your eye for brighter, more detailed views.Objective LensesThe 80-mm objective lenses offer plenty of light-gathering ability for superior low-light performance. The objective diameter-to-magnification ratio is ideal for scanning the skies, observing the Moon and planets, and exploring all the best deep-sky objects. Celestron SkyMaster Pro ED also makes an excellent choice for long-distance land-based viewing\u2014especially at dawn or dusk.The BodyCustom-designed rubber armor and a durable chassis protect your SkyMaster Pro ED binocular from damage without weighing you down. Viewing through SkyMaster Pro ED binoculars is comfortable for eyeglass and non-eyeglass wearers alike, thanks to the retractable eyecups and more than 15mm of eye relief. Eyeglass wearers can see the entire field of view while looking through the eyepiece with their glasses by twisting the eyecups down. For those who do not wear eyeglasses, the eyecups position the user\u2019s eye behind the eyepieces at the correct distance for optimal viewing.Ways to ObserveThe Celestron SkyMaster Pro ED binocular is tripod-adaptable. Use the built-in tripod adapter on the balance compensation rail to mount it on any standard photographic tripod or monopod for extended viewing or digiscoping (photography through the eyepiece). SkyMaster Pro ED\u2019s eyepieces are threaded to accept standard 1.25-inch astronomical eyepiece filters. Adding the right filter can deliver game-changing views for terrestrial and celestial observing. For terrestrial observation, filters can reduce the brightness of sand, snow, and water. For nighttime viewing, filters can cut glare, minimize eye strain, increase contrast, and even combat the effects of light pollution.<\/p>\n\n