When viewing distant objects through the use of a telescope, the most important part of that telescope is called the objective. The objective is that component of the telescope that has the ability of gathering the light that is available. Obviously, the larger the objective the greater is the capacity of the telescope to gather light which in turn allows the viewed image to be better visualized.
In addition, there are two types of telescopes. One type of telescope is called the refractor telescope and the other is known as the reflecting telescope. The difference between these two telescopes is how the light is captured.
Refracting and Reflecting Telescope
The refracting telescope obtains the light through its objective that is made out of glass. Basically, in this type of telescope, the glass lens is situated towards the front of the telescope. As the light is captured by the objective, it is then refracted or deflected through a lens which allows for the viewed image to be magnified. Examples of this type of telescopic equipment include scopes that are used on rifles, binoculars and spyglasses.
A reflecting telescope uses a mirror as its objective. This mirror is located towards the distal end of the telescope. In addition, the mirror has a concave shape. The curvature of the mirror allows for the midpoint of the mirror to be the focal point for all of the light that strikes each part of the surface of the bowl-like mirror. This reflection is then captured by the lens to view the item of interest.
Advantages Of The Reflecting Telescope
There are several advantages to the use of a reflecting telescope. The major advantage is that distortion of what is being viewed is minimal. This is because, through the use of the mirror, the wavelengths are all reflected consistently. This advantage also leads to the reflecting telescope being less expensive than the refracting telescope.
In addition, through the use of the mirror as the objective, the support for this mirror can be all along the posterior portion of the telescope. This allows for the housing to be very large which will accommodate a larger mirror. Larger mirrors mean more light which results in increased visibility.
However, as with anything else, there are a few disadvantages in the use of a reflecting telescope. One of those disadvantages is size. This is due to the fact that these types of telescopes can accommodate larger mirrors. This results in the telescope itself being larger which may prove to be an issue when storing or relocating the reflecting telescope.
In addition, because of the use of mirrors, there may need to be occasional adjustments made so that optimum light alignment is maintained.