The Dobsonian telescope, named after John Dobson who initially designed the mount that holds the telescope, is a reflector telescope by category. Utilizing mirrors to bring the light into the telescope, this is a great beginner’s model that is very affordable. The Dobson telescope is quite often referred to as a Newtonian telescope, one of the oldest and most popular types of modern reflector telescopes. The “Galilean” or refractor telescope, on the other hand, uses a series of lenses to collect the light.
Boasted as the best telescope for the cost, the Dobsonian telescope has a much wider aperture, or light gathering device, than other comparable telescopes at the same price. This simply means that the Dobsonian can pull in more light than other telescopes with a smaller aperture. And, the more light that the telescope is able to bring in, the more improved sights that can be observed through the telescope. This being said, if a good sized budget is available for a telescope, it could purchase a really large and powerful Dobsonian.
There are also a few disadvantages to the Dobsonian telescope, and the main one is their recurring need for realignment, necessitating more maintenance than its counterpart, the refractor. Misaligned telescopes produce poor resolution of objects being viewed through the telescope. Owning a Dobsonian will mean that it is imperative to learn and know how to collimate, or re-align, a telescope. Something else that will be imperative to learn in order to use the Dobsonian telescope to its full abilities is how to position the telescope unless, of course, it is computerized. The Dobsonian will require cleaning as well, unlike the refractor telescopes that necessitate almost no cleaning at all.
Computerized Dobsonians are on their own level, able to automatically pinpoint exact objects that the viewer wants to see. The downfall of computerized telescopes is that the person operating must know how to “tell” the telescope where to “look”, and for the beginner or the even slightly skilled star gazer, this could be confusing and frustrating. However, for the advanced or highly skilled astronomer computerized telescopes are almost irreplaceable. On evenings when the sky is clear, a computerized telescope could contribute to hours of non-stop, technologically enhanced sky patrolling.
The smaller Dobsonians are made with the intention to be portable. The lightweight structure of the hollow-tubed Dobsonian contributes to its portability, making it easier to carry. Since setting the telescope up is a breeze, it can be moved from the upstairs room to the outside for marvelous evening viewing whenever necessary.
As with all telescopes, the Dobsonian has its unique features as well as its disadvantages. For the beginner astronomer, the Dobsonian is a great investment because of its price and portability. If the willingness to learn more about the telescope and use it to its full capabilities, the Dobsonian can become one of the best purchases ever made. All in all, a Dobsonian telescope performs as a great economical telescope for the star gazer that is desires to further his education in astronomy without crushing their bank account, and should be strongly considered before making an initial purchase.