Telescopes- refractor or Schmidt-cassegrain?

[tuck]

What is one advantage of the refractor over the Schmidt-Cassegrain and
one advantage of the Schmidt-Cassegrain over the refractor?

[michael971]

refractors have a problem because they lens splits up the different wavelengths of light so that they do not focus at the same point.
To correct this telescope designers use glass called ED glass which is also used in the best quality camera lenses.
Even better is a mineral flourite, the material is made in a lab and is very expensive.

You might want to also consider Maksutov designs which are reasonably priced. They have long focal lengths and good for observing planets and double stars.
Meade has a Schmidt Newtonian design which is a reflector with a corrector plate. It is a short focal length and would be good for observing galaxies, nebulae and clusters.

[ghlo08]

Here is why I like the telescope, From my 35 years of experience as an astronomer who has used a variety of telescopes of different types along with using very rare large apertures of 8-12 inches. I have found the 6 inch F/15 refracting telescope is the optimum design for lunar, planetary, and solar observing. The telescope’s size makes it the best instrument in my opinion for advanced observers to use and simple enough for elementary observers to use for their viewing. An observer can master the telescope system with relatively few instructions, and yet the system is large enough to provide optimum viewing in city astmospheric conditions. Furthermore for more advanced observing the 6" F/15 refractor with it’s accessories provides opportunities for photographic and spectroscopic work as well. Observatories and educational institutions usually have found the 6-inch F/15 refractor to be the finest instrument for lunar, planetary, and solar observing. For those wanting to build a 6" F/15 refracting telescope system for their observing should obtain a copy of "Telescope Making44" and read the article entitled "Constructing a Large Brass Refractor" by Larry Myers. Telescope Making was a publication of Kalmbach Publishing Company (Astronomy Magazine)

[RussL]

To answer your question directly from my own experience:

The main advantage of MY refractor over MY SCT is portability, thus, I see more with it, more often.

The main advantage of MY SCT over MY refractor is it's ability to gather more light and to gain a much higher magnification. But these are advantages only when I require that kind of view.

My refractor is the Celestron 80mm Wide View f5 achro on an EQ-2 mount, 20.4 lbs.
My SCT is the Celestron Celestar 8 Standard f10 on an equitorial wedge mount, 39 lbs.

Otherwise, refractors have better contrast and sharper images than SCTs (some will disagree). SCTs lose contrast due to the shadow of the secondary mirror, which is large. But, compared to some other designs, the idea of an SCT is to give lots of aperture and focal length, but with a short tube for portability.

One is better than the other depending on the viewer's observing interests and criteria for portability. Long, large refractors are the best image producers, but very awkward to use and transport compared to other desings. Good for planets, the moon, and doubles, as well as gaining power for closing in on other DSOs that will allow it. Short refractors are splendid for wide-field views, and also produce sharp images. They are restricted to lower powers, though. That's not bad. Low power is often the best view. SCTs can give a lot of light gathering ability to help bring out faint objects, and their long focal length can give a lot of power. Typically, their images may seem a bit softer than those of refractors.

Oh, there's so much more to say, but I'm out of time for now. Read some more to study these differences before you buy one or the other. Think about what you prefer to view most.

Clear skies.