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Which type of telescope is the best? There is no simple answer to that question until you define your expectations of the telescope. Some telescope types allow for both terrestrial and lunar / planetary observing. Others are mainly intended for observing distant galaxies and other deep space objects, and may be completely unsuitable for terrestrial use. The images and brief descriptions below will start you on your way to understanding these different design types and their applications.

Telescope Bundles

Skies Unlimited is committed to providing you with high-quality astronomy telescope bundles and kits. Check out our Celestron telescope bundles online!

Dobsonian Telescopes

Dobsonian telescopes offer the most aperture for your dollar, and aperture is the most important factor when viewing deep space objects. Shop our Dobsonian telescopes!


Skies Unlimited is committed to providing you with high quality refractor telescopes and apo refractors. Check out our online store!


Our Schmidt-Cassegrain telescopes are very popular because they offer a combination of large aperture and a small and lightweight package. Shop now!


Our Maksutov-Cassegrains are a compact design that offer superior contrast and are excellent telescopes for planetary and double star observing. Shop now!

Newtonian Reflectors

Newtonian reflector telescopes are the most cost effective type of telescope for astronomical observations, offering the lowest cost per unit of aperture.

Solar Telescopes

Solar Telescopes allow you to safely observe solar prominences, sunspots, and other intriguing features of the solar disk.


An Astrograph is a telescopes designed designed for the sole purpose of astrophotography; they are not visual instruments.

Telescope Optical Designs

Newtonian Reflector Telescope

Newtonian Reflector Telescopes

Newtonian reflector telescopes are an optical design that use a mirror to focus light into a smaller area. Most of the larger telescopes in use today utilize mirrors for economic reasons. It is less expensive to produce a mirror than a lens, and that advantage grows with the size of the telescope. The main advantage of a Newtonian Reflector is cost per unit aperture. The disadvantage is the images they produce are upside down, meaning that they are not suitable for terrestrial observing.

Dobsonian Telescope

Dobsonian Telescopes

A Dobsonian telescope is a Newtonian reflector mounted on a simple yet stable alt-azimuth (lazy Susan style) mount. These telescopes are named for their designer, John Dobson, who sought to build a low cost large aperture telescope. No other design has had a greater impact on amateur astronomy in the past half century. Dobsonian telescopes are popular because they offer the most available aperture for the dollar. Dobsonian telescopes may appear unconventional to the first time buyer, but the fact is that they dominate the market for amateur telescopes over eleven inches in aperture. Wikipedia has a fine article on the history and origins of the Dobsonian Telescope.

Refractor Telescopes


Refractors or refracting telescopes are a design that use only lenses to focus the light; every other type of telescope relies on one or more mirrors to do that job. The long, slender optical tube of a refractor is the image that most people associate with a telescope. Refractor telescopes have the advantage of having an unobstructed light path, which produces higher visual contrast than other optical designs. Stars appear as pinpoints against an inky black background when viewed in a refractor. Refractors have the disadvantage of being the most costly per unit of aperture, which is why refractors tend to be smaller than all other designs.

Schmidt-Cassegrain Telescope

Schmidt-Cassegrain Telescopes

Schmidt-Cassegrain telescopes use both mirrors and a lens (corrector plate) to focus light into a smaller area. Schmidt-Cassegrains are popular due to their compact size relative to their aperture. These are the Jack of all trades in the telescope business. They are moderately well adapted to a wide variety of applications, including lunar, planetary, deep space, and even terrestrial observing. Variations on the Schmidt-Cassegrain design include Celestron's EdgeHD and Meade's Advanced Coma Free (ACF) optical systems. The primary advantage of a Schmidt-Cassegrain telescope is that it tends to offer the greatest degree of portability per unit of aperture. The disadvantage is they are more costly than Newtonian Reflectors.

Maksutov-Cassegrain Telescope

Maksutov Cassegrain Telescopes

Maksutov-Cassegrain telescopes are similar to Schmidt-Cassegrains, using both mirrors and a lens to focus light into a smaller area. Maksutov-Cassegrains replace the flat corrector plate of the Schmidt-Cassegrain with a convex meniscus lens. The secondary mirror is actually a silvered spot on the inside of the meniscus lens. This in itself leads to one major advantage: Maksutovs do not require periodic collimation of the optics as do Schmidt-Cassegrains and Newtonians. Maksutov-Cassegrains offer superior contrast to a Schmidt-Cassegrain, but they are also more expensive per unit of aperture.

Solar Telescope

Solar Telescopes

Solar telescopes offer a safe way to observe and study our nearest star: the sun. This is a highly specialized field and the number of suppliers is considerably smaller than that for general purpose telescopes. We offer solar telescopes from Lunt Solar Systems, Coronado, and DayStar Filters, that are filtered for the Hydrogen-Alpha and Calcium-K spectral lines. Often it is more cost effective to purchase a dedicated solar telescope than it is to add a solar filter to an existing one.

Feeling Overwhelmed?

Don't worry, this happens to a lot of people. If this is your first time shopping for a telescope, please take a few minutes to read our article Advice for First Time Telescope Buyers before proceeding any further. We think that you will be glad that you did.