Quoted:
Quoted:
Quoted: By the way, if you want a really good telescope that you can see things like the dumbell nebula and the ring nebula, get a 4" or bigger reflector. A reflector isalways better than the same sized refractor because a lens will refract different wavelengths different ways (and therefore turning the image into a rainbow at high magnifications), while a reflector does not.
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But reflectors have image degredation due to central obstructions. With the exception of Ritcheys, the best image will come from a premium apochromatic refractor, Period.
A perfect example of this is all the top amatuers that shell out 2 to 10 grand on a 4 to 6 inch refractor OTA from Televue, Vixen, Takahashi and the like over a 2 to 5 grand 8 to 12" computerized Cassegrain wonderscope.
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But mere mortals cannot see image degradation due to secondary obstruction.
For the BEGINNER, these scopes offer a much better bargin. Much easier to transport and set up. You can slip a 90mm Mak into a backpack and take it hiking. Easily. Not so with a refractor.
And then we have thermal effects. On the reflector, a simple dew shield solves most problems.
Astronomics.com is your best bet. Stay away from telescopes.com...
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I agree with most of what you say. I am not recommending a refractor necessarily, and not an APO for a beginner, I was just defending refractors from an absolute statement. If you see my first reply, I advise a 6" Newtonian or Dobsonian.
As advice for a beginner scope, let me also add that I would advise against the 90mm Maksutov Cassegrains. They are shiny, wizbang technical marvels with decent optical quality, however, their long focal length make them impractical for most astronomy other than planets. You can get some good looks at M42 AND M31, but you will hit your limits quickly aftrer that.
One more point, If you plan to get a Newtonian or a Dobsonian, make sure the focal ratio is at least f/6. Anything shorter (f/4.5 is common) at a beginner pricepoint is likely to suffer from significant chromatic and spherical abberation. I looked through one guy's 6" short tube reflector from Orion telescope (www.telescopes.com) and the image quality was horrendous, enough so where kids avoided it without being told.