Celestron SkyMaster Pro 20x80 Binocular - Astronomy Binocular Large Aperture Fully Multi-Coated Review (2026)

Optical specifications and what they mean for stargazing

The SkyMaster Pro 20x80 pairs 20x magnification with 80mm objective lenses, giving a 4 millimeter exit pupil, a figure that stays usefully bright for most observing conditions even though it is smaller than the 5 to 7 millimeter exit pupil of lower-power giant binoculars. Celestron rates the field of view at 3.2 degrees, equal to 168 feet at 1000 yards, wide enough to frame larger star clusters and comet tails in a single view rather than requiring the observer to pan the sky. Eye relief sits at 15.5 millimeters, and close focus is listed at about 66 feet, figures aimed more at distant astronomical targets and long-range terrestrial viewing than close-up use.

Build quality and weatherproofing

Celestron built the SkyMaster Pro line around a housing that is fully waterproof and purged with dry nitrogen gas, preventing internal fogging when the binoculars move between temperature extremes, a common problem when equipment is carried from a warm house into cold night air. XLT fully multi-coated optics and BaK-4 Porro prisms are intended to maximize light transmission and image contrast, both important at night when even small light losses through the optical path are more noticeable than they would be in daylight use. The rubber armored housing over a polycarbonate and aluminum frame is built to handle the bumps and occasional knocks that come with regular outdoor use.

Weight and why a tripod matters here

Celestron lists the SkyMaster Pro 20x80 at 86.4 ounces, or about 5.4 pounds, and at roughly 13 by 9.5 by 4 inches it is sized well beyond what most people can hold steady by hand for more than a minute or two, especially at 20x magnification where even small hand tremors become visible as shake in the view. A built-in tripod adapter is included specifically because Celestron expects most owners to mount these on a tripod or parallelogram binocular mount for any extended session, rather than trying to use them handheld the way a compact pair of birding binoculars might be used.

What's included in the box

The binoculars ship with a reflex sight rail for attaching an aftermarket red dot finder, objective lens caps, interchangeable flared eyecups to suit eyeglass wearers or bare-eyed use, a rainguard, a neck strap, a lens cloth, and an instruction manual, along with Celestron's limited lifetime warranty covering the optics. The interpupillary distance adjusts across a 56 to 72 millimeter range with a plus or minus 4 diopter adjustment, covering most adult users without needing a separate accessory, and the included tripod adapter thread is the standard size most astronomy tripods and binocular mounts expect, so a buyer rarely needs to shop for a separate adapter before their first session under the stars.

How it compares to other giant binoculars on the site

In the site's Best Giant Binoculars guide, the SkyMaster Pro 20x80 ranks first of seven, ahead of Celestron's own standard SkyMaster 20x80 and 15x70 models as well as bundled binocular and tripod packages from Celestron and Orion. Its top spot reflects the Pro line's more rugged, weatherproofed build compared with the standard SkyMaster series, though buyers should weigh whether the extra durability and coating quality justify the higher price over the standard 20x80, particularly for casual or occasional use where the differences may be less noticeable than for someone observing regularly through changing weather.

Frequently asked questions