>Stellarvue 80ED Raptor (carbon fiber tube) with dual-speed rotating focuser, collar and Vixen style mounting plate, collapsible dew shield, and case: $600 Poor eyepieces with a great scope will give mediocre results.)įollowing is a very good “entry level” ED-scope: Quality scopes do not come with eyepieces.
Newer designs are employing carbon fiber, which reduces weight considerably. Traditional refractor tubing was steel or thick gauge aluminum. A 2-inch dialetric diagonal will cost between $140 and $180. Also note that high-quality refractors do not come with diagonals. Installing a FeatherTouch or Moonlight focuser will typically add $300 to the cost of a scope with a generic dual-speed focuser. High-quality refractors will also sport dual-speed Crayford focusers.
Refractor telescope full#
The lenses used in ED or APO scopes will have full multicoatings that cheaper scopes will not. I would rate their performance at “9” to “9.5” for visual use (less critical than for those who image). Quality ED scopes are less expensive ($200-$300 per inch of aperture) for 80-mm and 102-mm class scopes. While 3-lens APOs give a “10” performance, they are the most costly ($400-$1,000 per inch of aperture) and are heavy. Refractors give clean and crisp views due to the sealed nature, unlike other telescopes like Newtonians which are subject to cooling and air turbulence issues.Īctually, high-quality “ED” refractors using two objective elements made of special low-dispersion glass can give near color-free performance. Refractor telescopes are very low maintenance due to being a sealed system and it is a simple case of setup and enjoy, without the fiddling lengthy setup times you may get with other telescopes. There are two main types of refractor telescopes: “Chromatic” – entry level and upwards with 2 lens elements and “Apochromatic” – premium, advanced and expert level telescopes with 3 or more very high quality lens elements with exotic mixes of materials.Ĭhromatic refractor telescopes are particularly good for observing bright objects such as the moon, planets and resolving things like double stars, but many astronomers who image deep sky and other objects use very high quality apochromatic refractors, due to their superior optics. So a 6 inch refractor gathers more light than a 2 inch one. The larger the size of the objective or primary lens = more light gathered. Different eyepieces give different magnifications. It is the combination of both which form an image that is further refracted and magnified by a secondary lens which is actually the eyepiece. Light waves which enter at an angle converge on the focal plane.
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