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Great places to find used equipment

Buying a Telescope

There are many resources available on the internet that will help you choose a telescope; however, some of these require a lot of care to filter through the information. The purpose of this page is to provide a brief guide to types of telescopes and answer some frequently-asked questions. You will also find links to excellent resources for those interested in buying.

First ask yourself “why do you want to buy a telescope?” You have probably seen beautiful color images of galaxies and nebulae and would like to see them for yourself. However, those color images were taken by amateur and professional astronomers with long time-exposure cameras and telescope mounts that are able to track accurately for hours. Don’t be dismayed; visual observing is extremely fun and rewarding. You just need to know what to expect.

The best way to start stargazing is by learning about the night sky. To start, let me give you three scenarios just to show you equipment you might find most useful and how much it might cost.

1. You want to learn about and be able to identify the constellations and study the mythology surrounding their establishment. What you need is a good star chart, maybe a field guide to the stars and planets (the internet is a tremendous resource), and a dark sky. Cost, $25. Your eyes will be your instrument.

2. In addition to the things listed in #1 you want to begin to explore deep sky objects such as nebulae and galaxies. You should invest in a good pair of binoculars. With a dark sky you will be able to see star clusters, the outline of many nebulae, and the moons of Jupiter. Cost, $50 - $150.

3. You want to explore deep sky objects in more detail. You want the ability to see a detail in star clusters and nebulae, see the rings of Saturn and maybe some detail on other planets. Here you may want to invest in a good reflecting telescope 8-10 inches in diameter (or even larger). Decent reflecting telescopes on simple altitude-azimuth mounts can range from $200 to $600 and up, depending on whether you buy new or used.

4. You want to explore deep sky objects and planets and use a film or digital camera to photograph them. Now, in addition to the telescope, you will need a mount that will track objects accurately at least for several minutes. The mount must also be very stable to minimize vibration. Equatorial mounts with motor drives range in price from $200-$300 to $10,000 or more. Again, it is possible to buy very good used instruments. Cameras range from webcams ($50 - $300) that will take excellent images of planets to film or digital single-lens reflex cameras. Digital cameras made especially for astrophotography can be purchased for as little as $200-$400, but you can easily spend $10,000 or more.