The Three Major Types of Telescope

Currently there are three main varieties of telescope existing today, each individual one with their own unique variety of benefits and disadvantages. The three types of telescopes are refracting telescopes, reflecting telescopes (Newtonian), and Catadioptric (or Compound) telescopes.

Refracting telescopes are generally what most consumers picture when they are referring to telescopes. They are the longer narrow, straight bodied telescopes which possess a nice straight-forward design of an objective lens and an eyepiece on reverse ends of the body tube. Refracting scopes were the original telescope style originating as long ago as the early 1600s. For a given aperture width, refractors continue to provides the greatest caliber image, possessing improved image contrasts, due to their straight forward and simple design. Refracting telescopes are usually additionally the most convenient to maintain, which in turn make these a perfect type for those stargazers who do not really want to spend a ton of time attending to and maintaining their telescope.

Typically the down sides of the refractor variety telescope happen to be largely due to its significant overall size. For the reason that they are the largest style of telescope, they're additionally the priciest for a specific aperture diameter. Moreover big telescopes tend to be more challenging to load up and setup, sacrificing portability as the overall size gets larger. An additional downside of a larger telescope is that if the mount or tripod that it happens to be fixed upon isn't secure enough, the telescope might suffer a loss of some of its stability during observing, resulting in images to bounce about or wobble.

The next type of scope, Reflecting Telescopes use parabolic mirrors to bounce light into an eyepiece which will produce an image. The most popular variety of reflecting telescope is known as a "Newtonian Telescope" and delivers the best cost for the specific aperture diameter. The actual eyepiece is positioned along the side of the body on the telescope. The contrast present in the reflecting telescope is identical to refracting telescopes if they're manufactured correctly, and because they have a much more compact body than refracting telescopes, they are considerably more mobile, steady, and as a result simpler to use.

The main disadvantage to this type of telescope is that the mirror in the bottom calls for the occasional alignment (often know as collimation). This technique is not as difficult as it may appear, nevertheless this type of toying around can be quite a put off to numerous amateur astronomers. Furthermore the model is more exposed to the ambient air and as a consequence must be cleaned out more frequently. Again nothing extremely hard however, some people desire a more hassle free telescope when it comes to maintenance.

Compound telescopes are the final type of telescope and are the most advanced design, using a mixture of reflecting light with mirrors, and refracting light with lenses, to make an ultra compact telescope that will provide you with the same magnifications and aperture sizes as bigger telescopes of different varieties. For a specified aperture size, these types can be sightly more expensive compared to a reflecting telescope but nevertheless less costly compared to a refracting telescope. The compound type tends to be a really popular choice because it offers the best of all worlds; good sized apertures, at a reasonable selling price, coming in a small and transportable size. Compounds happen to be also the perfect type of telescope for Go-To automated star tracking mounts. This is a good advantage for people who just do not desire to commit all of the time mastering the technique of object location and simply desire to invest more hours just observing.

The key limitation of compound scopes are that due to the fact the light becomes folded up within the frame of the scope so many times over, the interior becomes brighter, cutting down some of the contrast. Quite a few consumers find this downside to be an appropriate trade-off for each one of the aperture, cost, and portability benefits it gives.

For more information on the best telescopes be sure to visit http://www.stargazingtonight.com, a complete guide to the stars for those interested in stargazing.

Daniel Stewart is a Mechanical Engineer who also studied Astronomy and Astrophysics at Villanova University.

He is currently working on stargazingtonight.com, a website that aims to provide a comprehensive guide to the stars for those who are new to the world of stargazing, as well as a guide to the best telescopes available today

What is a Reflecting Telescope?

A reflecting telescope is one of two kinds of optical telescopes, refracting and reflecting. A reflecting telescope uses a single or combination of curved mirrors which reflect light to form an image. The reflecting telescope was invented in the 17th century as an alternative to the refracting telescope. The reflecting telescope was made to correct the server chromatic aberration that was part of working with a refracting telescope. Reflecting telescopes also create other aberrations, but they allow for a very large diameter which is helpful with research telescopes. The reflecting telescope comes in many designs which improve image quality. Reflecting telescopes are often referred to as "catoptric" telescopes.

There are many technical considerations to be aware of when using a reflecting telescope. Various aberrations are caused by the reflecting telescope, such as that the inner and outer zones of the telescope may not share the same focus. Spherical aberration can be eliminated with non-spherical mirrors.

Other aberrations are also common with reflecting telescopes. A coma may appear which is when a variation of telescope magnification may cause radial smudging which worsens at the edge of the visual field. Astigmatism may also occur around the focus of the aperture. Distortion of the field of view does not affect objects, but may harm sharpness. The best image plane is in general curved. This may not correspond to the detectors shape and may later cause focus errors. There are other reflector designs referred to as catadioptrics that correct some aberrations.

The majority of research-grade telescopes are reflectors. This is because, unlike a lens, the mirror does not need to be free of imperfections; it merely needs to be polished. Also, light of different wavelengths travels through a medium other than a vacuum at different speeds. The reflectors also work in a wider spectrum of light because certain wavelengths are absorbed when passing through lenses in comparison to reflecting off of them.

Alex Sutton has worked in the telescopes profession for nearly 11 years. For more information please visit telescopes