Quote:
Originally Posted by stevej37
Looking at the Celestron web-site....the StarSense Explorer telescopes.
Some are 'reflector' scopes and some are 'refractor' scopes.
What's the diff?...and which is better for a starter?
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A refractor is what most folks think of as a telescope, basically half of a binocular, or simplified, a tube with a lens at each end.
In a reflector the main lens is a concave mirror at the bottom of the tube that reflects up to another mirror near the top. The user looks through an eye piece that is perpendicular to the main tube axis.
Generally, when you make the objective lens larger, the telescope gets longer. In a refractor that can get big and unwieldy fast. In a reflector the tube length is effectively cut in half so you can get a much larger objective lens in a shorter package.
As stated earlier, a larger objective allows more light to be caught so often folks eventually trying to get the biggest that they can handle and afford.
I started with a 102mm (4") refractor. I eventually upgraded to an 8" Newtonian reflector (there are several types of reflector) on a Dobsonian bar because that's generally the way to get the biggest objective for the money. Refractor are usually on either equatorial or alt/az mounts which are taller and more expensive than the simpler cheaper and shorter Dobsonian mounts.
The two more expensive mounts are more likely to have some sort of tracking and the ability to tell it "i want to look at X" and it will point the telescope for you (of course that adds cost due to microcomputer and motor and gearing)
Dobsonian mounts are generally all manual. You have to point the scope at what yippy want to see. That's usually done via star hopping. Start on a bright elk known star, then bounce from dimmer star to star like connecting the dots until you get to the part of the sky that you want to see.