The Astronomical Unit


This page last modified 2006 August 18

Evaluating a Telescope in the Store

(To evaluate binoculars, click here.)

(Or, if it's arrived boxed, most of this is also applicable to what you can do in your home)

There is no substitute for taking an astronomical telescope under the stars, but this is too often not possible. Here are some pointers for things to look for "in store". It is your choice how you spend your money, but it is my strong opinion that you should be as aware as possible of any shortcomings before you buy. Almost all telescopes exhibit some of the "features" that these tests will reveal, but they are often present in greater number and severity in cheap telescopes. Many can be remedied – see the tutorial on upgrading a 60mm refractor.

Remember: Anything that is merely irritating in the shop will most likely become infuriating under the stars.

If the salesperson will not permit you to perform any of these tests, ask yourself why. Does the answer you get imply concealment, ignorance, reasonable caution, a pressured salesperson..?