Celestron 71017 SkyMaster 25x100mm Porro Prism Binoculars with Multi-Coated Lens, BaK-4 Prism Glass and Carry Case, Black

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In this article, I go through how the exit pupil, magnification and field of view are all connected and what you can expect to see with a powerful astronomy binocular. Orion binoculars are known for quality optics at a great price. We offer binoculars for every viewing interest, including astronomical binoculars, compact binoculars, waterproof binoculars, birding binoculars, and sport and hunting binoculars.

binoculars in 2023: Top picks for stargazing and more Best binoculars in 2023: Top picks for stargazing and more

When you use the Celestron TrailSeeker 8x42 binoculars, you'll notice that there is minimal false color. False color, also known as chromatic aberration, typically appears as a purple or blue halo around bright objects. In our review, we observed very little of this effect in the field of view, especially when observing the lunar limb.

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The Fujinon 16x70 FMT-SX binoculars are one of the most highly regarded astronomy binoculars available, at any price. They use a unique optical design that makes for an exceptionally flat field of view, which translates to tight star images very close to the edge of the field of view. The TrailSeeker 8x42’s minimalist design makes them a hugely more attractive option than large and heavy deep-sky astronomy-centric binoculars. All three binos showed actually less CA than I had expected (none of them has ED glass). The typical color fringes appear at the edges oft he moon’s surface in all three, but it is not very prominent and did in my view not disturb the observation much. Of the three, the Nightstar showed probably the highest level of CA, the Argus the lowest. Tip: The second number on the name of a set of binoculars is it's objective lens size measured in millimeters. e.g.: Celestron 25x100 Binoculars have objective lenses that measure 100mm in diameter.

SkyMaster 25x100mm Porro Binoculars | Celestron

Binocular lenses and prisms are often coated with anti-reflective material to minimize light loss as light travels through the multiple optical surfaces of a typical binocular. Coatings help maximize the amount of light transmitted through each glass surface of a binocular, so as much light as possible reaches the observer's eyes to provide a bright and sharp image. These are really important factors that directly effects the actual brightness of the observed image. The term used to describe this percentage of light that is not lost through the optical system is transmittance. During our hands-on Celestron SkyMaster 8x56 review , we thought they were suitable for astronomy and perform well across a wide range of observation environments, such as looking for birds, other wildlife and spotting athletes at the stadium. This will certainly add to image brightness and deliver an obvious improvement when compared to lesser quality instruments that are often only single layer coated or fully coated - but only on the external lens surfaces. Now that you're set-up, have a good look at your Celestron 25x100s, starting at the business end where you’ll put your eyes. The 4-millimeter "exit pupils" (the bright spots of actual image) look eerily small surrounded by the large-looking 20 mm eyepieces. But they're big enough to fill most adults' dark-adapted eyes. And the 15 mm "eye relief" (the distance from the eyepiece's surface to the last spot a full-width image can be seen) is long enough for eyeglass wearers to get a well-focused broad view. (Our Editors' Choice Runner-Up Orion Astronomy 20x80 binocularshas a slightly longer eye relief at 17 mm.) You probably won't even have to fold down the rubber eyepiece-guards.

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Most standard tripods can be used, but because you are looking upwards, it does mean that the eyepieces will be in an awkward position. To get around this, you either need to make sure you have a tripod that is tall enough so that you can get under it or use a chair and position yourself almost under the tripod. If I have to choose now, I would buy the Argus if money is no issue (Dennis in a recent thread here on CN rated the Argus best of all 25x100, and I tend to agree). I had only one sample of each model available, so some of the following statements need to be taken with a grain of salt (headword: „sample variation“). Celestron's SkyMaster line of large aperture astronomy binoculars offers exceptional performance at a great price resulting in excellent value for money. They are ideal for long-distance terrestrial encounters as well as providing a spectacular view of the heavens.