Maybe you’re an accountant, welder, or kindergarten teacher by day, but when the sun sets, you dream of wearing the hat of a backyard astronomer. If this is the case, you will need the most important tool of the trade — a telescope. So what should you consider when purchasing a telescope? Whether you want a closer view of the “man in the moon” or a “galaxy far, far away,” these tips should help you select the right telescope for your stargazing satisfaction.
Know Your Options
A refracting telescope uses a curved lens to gather light to form an image with excellent contrast while requiring little maintenance. However, these telescopes are more expensive and are known for the problem of chromatic aberration (a distortion characterized by fringes of color surrounding bright objects).
A reflecting telescope is less expensive and uses one or more mirrors to reflect light to form an image free of chromatic aberration. On the downside, these telescopes produce images with less contrast and cause stars around the viewing perimeter to resemble the appearance of comets. In addition, they require more maintenance because mirrors may need periodic re-coating and collimation (adjusting the optical alignment) is necessary each time the telescope is moved to a new location.
Beware of High Power
Inexpensive telescopes from discount stores may boast of high magnifications of 200-400x, but believe it or not, magnification is one of the least important factors in choosing a good telescope. Aperture (the diameter of the lens or mirror) is the most important factor since this is what determines how much light enters the telescope. The larger the aperture, the greater your ability to see objects deeper into space.
Try It Before You Buy It
Attend a local astronomy club event where you can “test drive” a number of different telescopes to see which one is a good fit for you. A staff member from your nearest planetarium can refer you to a club.
Visit a local telescope retailer so you can have your questions answered by a knowledgeable dealer. The salesperson will know the right questions to ask to help determine the best telescope for your individual interests and needs.
Don’t Forget the Accessories
Investing in a good telescope won’t do you much good unless you have a sturdy tripod to hold your image steady. You may also want to consider extra eyepieces, as well as various filters.
By Dondra Vaughn, Freelance Writer located in Georgia