You're wrong Joan. The central obstruction boogyman is just not real. You can split stars and look at planets just fine with a reflector and star clusters are really great in them. Of couse the view through the reflector is different from that of a refractor, that's because the resolution of the reflector is much better than the seeing will generally allow. But when the seeing settles down the extra aperture of a reflector blows away the refractor. It's painful for people to believe that a telescope of one third the price can have better views. But it's true. DT From: "jcarman6@q.com" <jcarman6@q.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Sent: Sunday, September 18, 2011 6:32 PM Subject: Re: [Utah-astronomy] Sept 17 Star Party Oh, is this going to be a refractor/reflector debate? Refractors do not have central obstructions. They take ALL the light from a source and focus it at a single point. This works exceedingly well on the moon and planets (and the spliting of double stars). Planets are sufficiently bright that it is not how much light gathering ability you have it is what you do with it that counts most. Light buckets like dobs are best on the faint fuzzies, where gathering as much light as possible is more important. Many years of comparing reflectors to refractors is backing me up. Given the same size telescope, same eyepiece, the refractor will display a sharper image of the moon or planet than a reflector. On the other hand, my refractor (or any refractor) will lose the challenge if it is the Andromeda Galaxy. Just try splitting epsilon lyrae with a reflector at 90 magnification -- footballs, if you are lucky. They can't do it. Of course, quality of the lenses and mirrors are an issue. Some refractors aren't up to the challenge, but it is the same argument with the quality of the mirrors. We won't get into focal lengths that add mud to the water. But that is why refractors have not died out and been completely replaced by reflectors. Refractors have their uses and their value and that is why they are still around today. ----- Original Message ----- From: "Chuck Hards" <chuck.hards@gmail.com> To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Sent: Sunday, September 18, 2011 3:33:20 PM Subject: Re: [Utah-astronomy] Sept 17 Star Party On 9/18/11, jcarman6@q.com <jcarman6@q.com> wrote:
The planets are best with a refractor!
Oh, Joan. (Chuck rolls eyes). I'm a refractor fan (have no less than 6 in progress as this is typed), but it's APERTURE that rules, everything else being equal. You know that. The planets are best with a big scope. Diffraction patterns are best with a refractor. ;-) _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php