For the past few days, I’ve done a lot of talking about differences between types of telescopes and mounting systems. On occasion, I’ve mentioned some of their parts, though I haven’t focused on that.
Today, I will.
This post is meant to be a brief overview of differences between telescopes and their parts. If you want some more in-depth explanations, I’ll link back to those I’ve already written.
In the image above, you see just a few different examples of telescopes. And just in this image, they range far and wide. Most stand on tripods, but some don’t. I can see two different telescope shapes. Some have the eyepiece in different places.
There are more variations of telescopes than are shown here.
So climb on board…I’m about to take you on a telescope tour!
Can you tell the difference between these two telescopes?
I’ll give you a hint. They are bothreflectors. I know I wrote before that you’ll normally find the eyepiece (the little bit tacked onto the telescope tube) on the side with reflectors, but as you can see here, this isn’t always the case.
Here’s another hint. The mounting setup isn’t the difference I’m talking about. I realize the most obvious difference is probably that one is on a “fork mount” (right) and the other is on an equatorial mount (left), but I’m thinking of something related to the optics.
Right next to light, the telescope is an astronomer’s most valuable tool. There are so many different varieties of telescopes, it can be hard to keep them all straight. But they can all be sorted into a few basic types, and that makes choosing one a lot simpler.
Two very common types are reflectors and refractors, and each one in the image above is one of these. You can tell a reflector by its cylindrical design. They all look like cylinders, you say? Well…refractors are a little bit different.
Take the two telescopes on either end of this lineup, for instance. These two—the far left and the far right—are refractors. And you may notice that, unlike most of the rest, they’re not perfect cylinders.
Look closely. You’ll see that, not only is the end pointing up a bit wider than the rest of the telescope, but there’s a little tiny piece tacked onto the end. That same little tiny piece is tacked onto the side for the reflectors.
Every reflector and every refractor can be recognized by these basic qualities. But what they do with light is more important.