Google it - be prepared to be overwhelmed at first. Most refracting telescopes use two main lenses. This type of telescope is called a refracting telescope. They focus the light and make distant objects appear brighter, clearer and magnified. CFF Telescopes Apo Refractor Telescopes Whether you are a resolute visual observer or dedicated astro-imager, refractor telescopes offer unique advantages. Suggest you go out to the various manufactureres sites: The earliest telescopes, as well as many amateur telescopes today, use lenses to gather more light than the human eye could collect on its own. Then there are the "quads" - I don't know too much about them so I cannot comment. The best cost 3-to-4 thousand ( and more ) new. A very good 100 mm triplet can cost about ( roughly ) $2000 right now. This allows more tack-sharp color astrophotographs. ( someone experienced please correct me if I have the spectrum components wrong ). Then, Triplets, 3 objective lenses that focus the Three crucial ( red, violet-blue & green ) wavelengths to approximately the same focal point. These are best for visual observation but can also be very reasonable in cost - even in a 4-to-5 inch scope. There are basically ( keyword ) several different categories of REFRACTORS: 2 objective lens models ( doublets ) that CAN ( but are not always ) made of Extra-Low Dispersion glass. I am looking into astrophotography ( right now ) as well. Lots of beginners go with an even larger diameter and just as long a Newtonian REFLECTOR. Sure a beginner can use it - if you want. As an example, the Celestron C6-RGT is a 152mm objective, 1200 mm focal length, 50.5 in longį/ 8 with equatorial mount is about 68 lbs total weight. a "slower" scope or lens ) lets in less light ( photons ) per unit time.ġ50 mm refrators are 6" diameter scopes - that's a pretty hefty piece of glass. Larger diameter scopes gather more light.įaster scopes ( eg, an f/5 versus an f/8 ) will provide you with quicker exposures. You can buy a fine 80-mm apochromat for a much more modest cost.įirst rule - APERTURE RULES. Also much cheaper - a mount capable of doing long-exposure astrophotography with a 150-mm refractor is likely to cost at least $1,000 for the mount alone - and you'd do much better if you spent much more.īeside size, what is the downside of a refractor compared to a reflector?Įither you buy an achromat and end up with lots of false color - not recommended in particular for astrophotography - or you buy an apochromat and end up spending a huge amount of money. If you want to undertake long-exposure, deep-sky astrophotography it will be much, much easier with a smaller telescope. My primary interest is in photography and I know the aperture part is good but I've read where they are for intermediate or advanced amateurs. In my opinion, other designs seem more practical in those sizes unless you happen to have a very specific need. However, a 150-mm refractor is mighty big and heavy. Are the 150mm size refractors (or bigger) for beginners? I have a question about the bigger refractor telescopes.
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