Telescopes are devices used to magnify and accentuate the space objects. With a telescope, you can get into the faraway galaxies or watch planets on the surface. There are mainly two types of Telescopes- Reflectors and Refractors.
Reflector Telescopes use concave mirrors, and are short and wide usually. They are used to get into deep space and far off galaxies because of their high aperture ranges and extremely high light-gathering abilities. Because the light enters into the tube and then bends inward, it creates a bigger space for light to enter giving clear pictures. They are often cheaper in price and easily available, and because of shorter length, they are extremely portable. One very big drawback with reflector telescopes is that they show an inverted image which means that if you use them in the daytime, you would see things hanging upside down.
They use lenses and not mirrors, which are convex in nature. They are often used for on-the-surface space imagery, such as the locating the Moon and the planets. Their bodies are slim and long, and the tubes are sealed making them very low-maintenance and good looking. Their best feature is that they give ‘right-side-up’ images and image distortion is the least in the Refractor Telescopes. Because of the use of the lenses, though, they suffer from chromatic aberration, a phenomenon caused by multiple wavelengths of light entering through the same space. Refractor Telescopes are more expensive and generally start with a 3” aperture.
Which one is the best?
When we talk about a refractor, its best quality is that it does not obstruct any light but in the case of a reflector telescope, because of the second mirror, a bit of light is blocked. This also causes the images to be a bit clear and sharp in the case of a Refractor Telescope. Because of a rigid structure and a straight, unobstructed optical path, Refractor telescope makes one which astronomers would usually use as this feature makes it extremely low-maintenance. But a big drawback in the case of refractor telescopes is that they cause chromatic aberration, explained above.
Reflector telescopes have mirrors, making light pass through in its true form and colors. They can have high aperture ranges and are portable, just a little problem where one has to incorporate a few adjustments to set the optical alignment of the mirrors. Reflectors are also inexpensive as compared to the Refractors as it is less expensive to make good quality mirrors than to make good quality lenses. A reflector telescope is the best cheap telescope.
When it comes to choosing one, it really depends upon your requirements. If you need a high definition quality of imagery and you want to work with greater aperture and light settings you can always go for Reflector Telescopes. They are a bit complicated to use but if you are an intermediate or higher level astronomer they would work just fine for you and would not be as complicated.
If you need to do stargazing, that too in a good quality, or if you are just a beginner and want to explore the space, Refractor Telescopes would work just fine for you except for the fact that they are a bit expensive and that you would really be able to go very deep into the space. With the chromatic aberration, the colors might distort which is also a bit of a drawback. But for beginner level astronomy you can always go for Refractor telescopes.
Other categories that you might find suitable to your needs
These are a hybrid type of telescopes with both of Reflector’s and Refractor’s qualities. They use both lenses and mirrors and are good for watching stars, the Moon and the planets. They are highly portable, low-maintenance and the best part about them is that they have eliminated the limitations of both the types and kept the qualities of each such as the images being the ‘right-side-up’. This makes them more likeable and they work as good with the beginners as with the intermediate and high-level astronomers.
So finally it all depends upon what your requirements are, how new or old you are to using telescopes and what do you really expect out of the output. Choose wisely.