The Celestron AstroMasters used to come with a strangely designed, cheap, built-in, non-removable red-dot finder that had a nice switch and glass window, but suffered from alignment problems. The 10mm Kellner supplied for medium power (65x with the 130EQ) works well, and thanks to its much greater and more reasonable apparent field of view (around 50 degrees) it actually achieves a similar true field to the 20mm Kellner. Galileo himself would probably complain about the abysmally low quality of this eyepiece. It’s also a bit too much magnification (33x) to be a great low-power “finder” eyepiece, and thanks to its narrow apparent field, it only gives a true field of view of 0.9 degrees-less than two full moons across, making it difficult to find many objects. This useless gimmick of a feature has resulted in an eyepiece with a roughly 30-degree apparent field of view, lots of internal reflections and light loss, fuzzy images, and an almost entirely plastic build. All of the AstroMasters are advertised as usable for terrestrial viewing because Celestron has managed to convince consumers that a Newtonian reflector on an equatorial mount is designed for such use. As for why Celestron supplies it, the answer is simple. This eyepiece is identical to the one supplied with Celestron’s PowerSeeker scopes. The 130EQ, like all of the AstroMaster Newtonian reflector models, comes with a 20mm erecting Kellner eyepiece for low magnification views. One of the rings has a small ¼ 20 threaded screw/knob that allows you to piggyback a DSLR on top – if the mount is motorized with an aftermarket clock drive such as Celestron’s Logic Drive, it will work well enough for wide-field astrophotography. The tube attaches to its mount with a pair of felt-lined metal tube rings and a short Vixen-style dovetail, which allows the scope to be balanced and the eyepiece rotated to a comfortable position, as well as for the scope to be installed on a different mount. Both the primary and secondary mirrors are fully collimatable, and the focuser is a standard plastic 1.25” rack-and-pinion unit. The rest of the 130’s optical tube is fairly standard in its design and function. This alone disqualifies the AstroMaster 130 from being a serious recommendation in our book. One should not have to play the lottery to get a decent instrument with hundreds of dollars on the line, and Celestron should be able to give a concrete answer as to the nature of their product. When consulted, Celestron gives varying answers as to whether the AstroMaster 130 scopes are sold with spherical mirrors or not. The bulk of the AstroMaster 130 scopes I’ve seen have had acceptable primary mirrors–usually not quite parabolic but not quite spherical either–but a few have had spherical primaries that made for mushy views. These mirrors cannot focus light correctly (a proper Newtonian telescope uses a parabolic mirror), and they make the telescope nearly unusable at high magnifications. Seemingly as part of an effort to reduce manufacturing costs and maximize profit, Celestron is putting spherical primary mirrors in at least some of its AstroMaster 130EQ units. However, trouble has arisen with the AstroMaster 130EQ scopes lately. At least on paper, it’s identical to Celestron’s StarSense Explorer, Omni XLT, Astro-Fi 130, SkyProdigy 130, and NexStar SLT 130mm telescopes, as well as the venerable Astronomers Without Borders OneSky, Zhumell Z130, and others. The Celestron AstroMaster 130EQ is a 130mm f/5 Newtonian. Overview of Astromaster 130EQ Optics Performance
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