What is the single most important thing I should know before buying a telescope?
This is the single most important thing you should get out of this FAQ: DO NOT BUY YOUR TELESCOPE FROM A DEPARTMENT STORE. Ignore everything any literature tells you about magnification and such. Buy from a telescope store, where you will get a telescope that makes smaller claims, but will give you FAR better performance. The reason is that as far as telescopes go, how much you can magnify is a function of the amount of light the telescope receives, which is almost entirely determined by the telescope’s aperture (the size of the lens or mirror that points at the sky). As far as magnification goes, you can expect 50x per inch of aperture on a normal night. Department stores always show little 2 1/4 inch refractors from 125+ dollars and say that the refractor can get up to a whopping 600x or so. Strictly speaking, this is true. However, applying the 50x rule, it is easy to see that 125x would be pushing the optics, and that is assuming that they were high quality ones. With the quality o
