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Beginner's Question

Started by tdmiller, 06/26/2012 01:53PM
Posted 06/26/2012 01:53PM Opening Post
I am very new to the world of telescopes and astronomy, so this is a real beginner's question. I have a Meade LX200 10" telescope. Would it be categorized as a Reflector or Refractor telescope.

Thanks for your help.

Tom Miller
Posted 06/26/2012 02:22PM | Edited 06/26/2012 02:28PM #1
Hi Tom. The answer to your question is "Yes!" wink

Well, that's the smart-aleck answer, but there is a bit of truth behind it. Your Meade 10" is classified as a catadioptric telescope. Popularly denoted as a cat (for short), a catadoptric telescope uses both lens and mirrors to bring the incoming light to a focus and produce an image. Your Meade can be also classified further as a Schmidt Cassegrain. The lens in the front was designed originally by Bernhard Schmidt and the secondary mirror is a convex surface, making the overall system a type of Cassegrain telescope.

The following is just my personal opinion. If someone told me to limit my choice to refractor or reflector, I'd say that your Meade 10" is a reflector. The mirrors do most, nearly all of the focusing. The lens actually corrects for "errors" in the focusing by the spherical mirrors (should not be spherical for a true Cassegrain) and actually allow Meade (and Celestron) to make spherical mirrors*, an easier job. The lens is more often just called a corrector.

* If your Meade is an "ACF" )Advanced Coma Free), the secondary mirror is not spherical. It is built so that it, the primary mirror, and corrector work to produce an image similar to that produced in Richtey-Chretien telescopes (hyperboloidal primary and secondary mirrors).

Best Regards,

Mark Costello
Matthews, NC, USA

"I hear you're mechanically inclined. Did you ever do anything with perpetual motion?"

"Yeah, I nearly had it a couple of times."