Star clusters you will know If you are ready to take the next step and buy your first Telescope.
Purchasing a new telescope can be baffling, especially for the first timer. And most of us are left wondering, so which telescope is for me? Understanding telescopes and their various accessories can go a long way in choosing the best one for you. Whether you are an amateur astronomer or veteran pathfinder, here are a few basic ground rules that will help you better identify the different types of telescopes and help you opt for the ideal one for you.
Aperture of a Telescope
A telescope's most important attribute is its aperture, which determines the brightness and sharpness of everything you see through your scope. Technically, this is the diameter of the main lens or mirror and as the aperture increases so does the details of the image you see. Depending on the aperture you will either see an open or a restricted field of view. For example a good 10" aperture scope shows sharper images than even a well-made 6" aperture telescope.
But since aperture is so important, many astronomers are misled into believing that getting the biggest aperture you can afford is the simplest way to choosing the best telescope for you. However in practice it's not so straightforward. If you make your decision based solely on the size of aperture, you might end up owning a massive telescope that sits in a corner gathering dust.
Ask yourself, where will I want to use my new telescope? If the answer is nearby in the backyard then having a large telescope will be of advantage to you. If you need to carry the telescope to darker skies away from city lights, you will definitely need something compact, yet powerful. And don't forget that you may have to assemble and set up your telescope in the dark making it even more difficult. And a scope that is too huge to carry outdoors and too long-drawn-out to set up, will rarely be of use.
Power or Magnification of a Telescope
Keeping aperture in mind, consider other important aspects like power and design before you make up your mind about the telescope you would like to purchase. Power is the magnification that the telescope can offer. This is a critical factor since it decides how close a view you can get of the space and planets. But it is not a decision making factor. You can make any telescope magnify at effectively any power you want by using different eyepieces.
An eyepiece is the small removable lens assembly you look into. Most telescopes come with several eyepieces and you can buy more separately. Remember to match the power of your eyepiece lens with the aperture of your scope for clear images. Using a very high power lens with a small-aperture telescope will show a highly magnified fuzz while with a large-aperture scope can show a meaningful image even at 200x or more. In either case, the lowest powers are the easiest to use, especially for beginners, and provide the most pleasant views. More to come in my next entry.
