Schmidt-Cassegrain Telescopes

Video Transcript

"So today I'd like to show you how to set up a different type of telescope than, that you've not seen before. This one is called a Schmidt Cassegrain telescope. The previous types that you've seen are the Newtonian Reflectors and a Refracting telescope. So this one is a different type in that it combines kind of the two basic principles of the other telescopes in that it uses both lenses and mirrors. So first let's go ahead and set it up and I'll go over some of the basics with you. Okay, so this is the basic set up for a polar aligned Schmidt Cassegrain telescope. Now the name is a little bit more complicated than most telescopes and it's due to two factors. So the Schmidt part refers to this glass plate that's in front here. So in the reflecting telescope, you would see little rods that were holding the secondary mirror. And the Schmidt Cassegrain telescope, the secondary mirror is held in place by a corrector plate which is this glass plate. The Cassegrain refers to the mirror in the very back. So just like a Newtonian, the mirror is set up in the back and it shoots the light forward where it hits the secondary mirror. In this case however, instead of shooting light out the side of the telescope, the secondary mirror then redirects the light out through a hole and the primary mirror. And ultimately, the light reaches the eye piece in the back of the telescope."