![]() German equatorial mounts can often place the eyepiece of a Newtonian in an awkward position, and you must rotate the tube in its rings to reposition it somewhere more comfortable. ![]() You can also equip the mount with Celestron’s logic drive for hands-free tracking. The CG-3 has flexible slow-motion cables for both axes and fine adjustments in altitude, and has an azimuth for accurate polar alignment. The mount also has a Vixen saddle, so it can accept other optical tubes interchangeably with no tools needed. It has 1.25” tubular steel legs and lots of plastic castings on the tripod. The CG-3/CG-2 is of the run-of-the-mill, cheap, and German equatorial design, with tiny, useless setting circles that are little more than decoration. Celestron’s CG numbering system is confusing they should ditch it and stick with the EQ1-8 system that other companies use. The mount Celestron supplies with the AstroMaster EQ telescope is known as the CG-3, though some literature refers to it as a CG-2. One of the rings has a captive ¼ 20 knob, so you can piggyback a DSLR camera on top, but this will further wreck the balance, and is too much for the mount to handle anyway. The Celestron AstroMaster 114EQ comes with standard tube rings and a very short Vixen dovetail, which would allow you to put the scope on a different mount, although this is the equivalent of putting premium dipping sauce on McNuggets-the prime ingredient is still cheap and the secondary ingredient is never going to compensate for that. The finderscope is a standard StarPointer red-dot finder, though until recently, most AstroMaster scopes had an obnoxious and often-faulty built-in red-dot finder. The focuser on the AstroMaster 114EQ is a modest and functional 1.25” rack-and-pinion, mostly made of plastic, apart from the knobs. This strains the mount and is a nuisance while observing, as you will always have to tighten the declination axis. The giant casting with the AstroMaster logo that protrudes nearly halfway along the tube, as well as the area around the focuser, means that you cannot slide the tube in its rings to achieve balance on the declination axis in most situations. Moving on to the mechanical aspects of the OTA, we come to another problem: the plastic castings. As a result, the 114EQ cannot achieve decent images even when well-collimated, which itself is hard to do. The correctors in these scopes are incredibly cheaply made and aren’t remotely close to the right shape, being glorified cheap Barlow lenses. So the correction is constantly varying depending on what eyepiece is used or even who is looking through the telescope. Second, it means that the spacing between the corrector and the primary mirror is not fixed, but instead varies depending on what eyepiece you’re using and also whether you’re nearsighted or farsighted. This causes two problems.įirst, it can’t easily be removed, which is basically required to collimate the telescope precisely and achieve sharp images. Celestron’s Bird-Jones design places the corrector lens inside the focuser. Furthermore, Celestron didn’t even bother to execute the design correctly. The cheap Kellner eyepieces supplied with many entry-level telescopes today would’ve amazed a 1950s amateur with their quality and work well enough with even a relatively fast focal ratio telescope. The Bird-Jones design is outdated and no longer needed. At the time the Bird-Jones was designed, eyepieces were simple and coma correctors were nonexistent, so focal ratios tended to be on the long side to achieve sharp images. This design allows for the secondary mirror to be shrunk down, the primary take the shape of a sphere that is easy to make (cheap), and allows for a stout and stubby telescope that has a long focal ratio and next to no coma. It’s a Bird-Jones (or Jones-Bird, depending on who you ask).Īs originally designed by Bird and Jones, this catadioptric design uses a spherical primary mirror with a corrector lens just before the secondary mirror. So what’s going on? Well, the AstroMaster 114EQ isn’t actually a Newtonian. This should immediately raise some eyebrows, as the optical tube of the telescope is obviously way too short to accommodate such a focal length. The Celestron AstroMaster 114EQ is supposedly a 114 mm Newtonian reflector with a focal length of 1,000 mm.
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