Chapter 1: Why do you need a Telescope?

This chapter explains the uses of a telescope and helps you determine if a telescope is what you require for your viewing needs. The 2 basics features of Telescopes are also explained to give you an idea of what to look out for when buying a telescope.

Why do you need a Telescope
To buy or not to buy a Telescope? Seems like a basic question, but a very important step in getting the right scope to suit your needs. Most individuals purchase their first telescope thinking their purchase provide excellent views of both land and astronomical objects. Truth is, no matter how attractive the thought of an all round telescope is, the common rule is land-based viewing telescopes rarely excel for astronomy, with the same applying to telescopes for sky viewing. We recommend that you decide which type of viewing you will be doing more of. If you are interested in doing more land viewing, you should consider a spotting scope or a pair of binoculars. You can learn more about these different options at our Beginner's guide to Binoculars and Beginner's Guide to Spotting Scopes.

What do I look for in a Telescope?

The telescope's main function is to redirect light to a desired particular point through a lens. Various lenses offered various magnification. In short, a telescope collects and focuses light.

The size of the aperture will determine how much light is captured. More light, also means greater clarity in the images you see. Because astronomy is carried out in poor light conditions, having a large aperture means the maximum amount of light is captured for a bright and sharp image.
What is Aperture of a Telescope?
A telescope's aperture (or light gathering ability), is thus its most important feature. The aperture is measured by the diameter of your telescope's main optical component.

Before you get too excited about aperture there is a small word of warning. Many people are misled into believing that getting the biggest aperture is the simplest way to choosing the best telescope. What they don't realise is that the larger the aperture the larger the telescopes and big telescopes don't always suit everyone.

Try asking yourself, “Where do I want my telescope to be placed and used?" If the answer is in the backyard, or nearby, then having a large telescope will be great. If you intend to carry the telescope to darker skies away from city lights, you will definitely need something of a smaller aperture but still powerful. A large scope is troublesome while travelling, while a smaller scope in a convenient location may not give as great an image as a larger scope can. So think about how large you want your telescope to be.

Magnification is an important concept to understand when choosing your telescope. Some will tell you that magnification (or some call it 'power') should determine what telescope to purchase.

Lets get it straight, magnification is important but not a decision making factor.

The magnification of your telescope is determined by the eyepiece you use. Changing magnification just involves swapping your existing eyepiece with one that has a higher magnification.
Magnification is not the most important consideration when choosing a Telescope
Essentially any telescope can have an infinite range of magnification. So don't get too excited by telescopes that promote a large magnification. It may be possible to get 800x but at that magnification you just highlight air particles between your telescope and the object you're looking at. What would be the point of magnifying an image from a small aperture telescope that doesn't produce a clear image in the first place.

A good analogy would be a television screen. If we go too near the TV (i.e. magnify too much) we end up seeing mere screen pixels. It is only at an optimum distance when the image we see on the TV screen becomes clear.

Chapter 2: Types of Telescopes