25 X 100mm SkyMaster


Availability: More on the way

Make no mistake about it. At 157 ounces (9 lbs., 13 oz.), Celestron's 25 x 100mm SkyMaster is a big binocular, in weight as well as performance. At its modest price, it is also a startlingly economical big binocular . . .
Our Product #: C25100
Celestron Product #: 71017

Product Description

For no more than the price of a single 4" economy telescope, the Celestron 25x100mm SkyMaster binocular gives you the light gathering capacity of two 4" rich field refractors - one for each eye. Using two eyes to observe increases the resolution of small details by as much as 40% over the resolution visible when using only one eye, as you do when looking through a telescope or spotting scope. With its immense light grasp, it offers admirable astronomical viewing on its own, as well as serving as a good wide-field observing complement to the narrower field of a telescope.

The Celestron 25x100 has a good 3 degree field of view and excellent resolution, so it excels at capturing large nebulas like the Lagoon and the Veil, scanning the Great Galaxy in Andromeda or M33 in Triangulum, taking in open clusters like the Beehive and the Wild Duck, and more. It is waterproof, something rarely found in a binocular in this aperture and price range. That means you don't have to worry about damaging the binocular if you set it down in dew-soaked grass or a puddle after observing. It has a pebble grain finish that provides a sure grip if it gets wet.

A reinforcing bar runs from the prism housings to the objective lenses. In addition to providing structural rigidity that keeps the optics firmly collimated, the bar provides a sturdy support for the integrated photo tripod adapter. The tripod adapter can slide along the bar to balance the binocular on a 35mm or video tripod, no matter what part of the sky you are viewing. Once you find the correct balance, a large thumbscrew locks the adapter in place. 

Using the binocular on a tripod is virtually mandatory, as few people will have the wrist strength needed to hold them steady enough for extended hand held use. The supplied lightly padded neck strap is acceptable for occasional use. However, adding a wide heavily padded neck strap such as the one listed below would be a comfortable addition if the binocular must be carried extended distances to an observing site.

The SkyMaster uses high light transmission BaK-4 prisms and multicoated optics for bright images of faint deep space objects. There is some barrel distortion (straight lines at the edge of the field are curved), and some visible astigmatism and chromatic aberration at the edges of the field. However, these flaws are minor considering the SkyMaster's 100mm aperture and are unobtrusive for all but the most critical and nitpicky of observers.

The usable eye relief is somewhat limited, at 10mm. This will moderately vignette the image for most eyeglass wearers. Unless you have severe astigmatism, if you wear eyeglasses, you'll get the most impressive views with your glasses off. Soft rolldown eyecups shield the unaided eye from stray light when rolled up, and cushion eyeglass lenses when rolled down. The SkyMaster eyepieces focus individually, in keeping with its designed use as a strictly long-distance observing tool from a tripod-mounted fixed location. 

With a close focus of 80 feet, this is not a general-purpose birding binocular, so fast center focusing is not needed. While you can't look at warblers close up, the SkyMaster is a good choice for long distance terrestrial viewing under low light conditions. Nesting eagles, deer across a meadow, or ducks across a lake at dusk are prime candidates for this big binocular. As a serious astronomical observing tool, as a long distance nature study instrument, or as a highly useful companion to take into the field with your telescope at night, the big Celestron 25 x 100mm SkyMaster is a very worthwhile balance of very big performance versus very sensible price.

Tech Details

Weight 9 lbs 13 oz
Warranty Limited Lifetime


Review by:
These binos have given me a good and economical start in astronomy. I put them on a pistol grip mount and an inexpensive Celestron tripod and have been taking them to star parties. I was surprised at the quality of optics and ease of transport, setup, and use. The only drawback is with viewing directly overhead. The tripod setup that I have will just not accomodate this, and a parallelogram mount is really the best answer but too expensive right now. I am not comfortable above 70 degrees. The 25X gives does very well on deep sky objects and the wide field of view makes finding them easier. In fact, I usually beat all the telescope finders. I store the binos on the tripod in front of a picture window and use them for terrestrial viewing there. They do very well for this day and night. I highly recommend these 25X100 binos becouse of the affordable quality, power. and wide FOV. A good tripod is essential. (Posted on 11/27/2018)
Review by:
I find my little grand kids don't really have the patience to stick with me while star gazing with my Mak-newt telescope. At least not yet! These are the answer. It takes seconds to stand them on a tripod and find something to look out up there. We can clearly see the moons around the planets, Saturn's rings, etc. You do need a pretty duty heavy tripod. They really did exceed my expectations. (Posted on 11/13/2018)
Review by:
I own a questar telescope but bought these as an even quicker "set up a see" what's out there . For the money they are amazing with very good resolution and very little distortion on the edges. Yes they are heavy but hand holding them for about a minute is just about doable . I am tall so finding a tripod to be able to look through them when near vertical was a challenge but managed to find one so no more stooped back or cricked neck. Having almost stereo vision with them is very easy on the eyes. Would throughoughly recommend. (Posted on 10/7/2018)
Review by:
You need a very sturdy mount for this binocular to provide the stability you need to truly enjoy the view. I've used them for both astronomical and terrestrial viewing. The optical quality is quite good for the price, not as good as my Fujinon 16X70's but half the price of the Japanese pair. (Posted on 10/6/2018)
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