Your First Telescope - an Astronomy Net Article

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Your First Telescope
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Your First Telescope
"Which one should I buy?"

by
Ed Ting

So, which one should I buy?

Depends. The "right" telescope depends on you, your observing habits, and your financial situation. Picking a telescope used to be a simple matter. You started out with a 60 mm refractor (probably from a department store), then you upgraded to a 6" f/8 reflector from either Criterion or Meade, and if you stuck with it long enough, you eventually bought an 8" Schmidt-Cassegrain from Celestron.

My, how things have changed. Throughout the 1960 and 1970's, the Newtonian reflector ruled the amateur roost. From about the 1980's onward, astronomers flocked to the portability of Schmidt-Cassegrains as both Meade and Celestron duked it out to try and out-do one another on features. Then, the refractor, long given up for dead, came roaring back with the advent of ED and fluorite glass. Now, you see all three designs in use regularly.

The advantages/disadvantages of each design are well-documented elsewhere, so I'll attempt to give you some "other" information which may be useful to you.

Despite the optical superiority of good refractors and the lower cost of reflectors, most astronomers still wind up with Schmidt-Cassegrains as their primary instruments. It's not hard to see why. A 10" S-C is relatively affordable and portable. A 10" reflector is a handful, especially an equatorially- mounted one. And a 10" refractor? Forget it -- you'll probably need a separate observatory to house one.
4.5" or 6" reflectors make excellent beginner's instruments. For $300-$650, you get a decent aperture and a scope that's relatively portable. On the refractor side of the table, look for an 80 mm scope on a stable mount.
Avoid like the plague any cheap refractor sold on the basis of its magnification. A "675X" 60 mm telescope is almost certainly a piece of junk. Maximum useful magnification is usually given as 50X-60X per inch of aperture. Thus, the 60 mm example given above is really only a 120X-144X telescope (and its images will probably break down well before that point, to boot). You find these scopes all over the place, in department stores, toy stores, "Science & Nature" centers at the mall, etc.
Let me repeat that one again: Do NOT buy a telescope from your local depart- ment store, toy store, or from a television mail-order program. Most scopes found at the Nature/Science stores at your local mall also fall under this category. These telescopes are little more than toys and will likely kill your budding enthusiasm. Buy from a retailer who specializes in serious amateur telescopes. Some of the better ones are linked off my "links" page. As a general rule, avoid any telescope that costs less than $300.
On the other hand, if you're the type who always has to have "the best" (and can afford it), consider a modern ED or fluorite refractor. I should point out that a world-class 4" refractor will cost you well over $2000 for the optical tube assembly alone. Scopes in this category include the TeleVue 85 and 101, the numerous Takahashis, the Astro-Physics refractors, and the apochromatic models by Vixen. Other scopes in this category include the Maksutovs by Questar ($4000-$12000, depending on model, less, if used.) Questars are built like precision scientific instruments, have a cult-like following, and seem to last forever, but they are not ideal beginner's instruments in my opinion.
I'll say one thing for Newtonians. They're the most comfortable to use of the three designs. The eyepiece is nearly always at a convenient height. Refractors are the worst in this regard. Looking at anything near the zenith with most any refractor is a less-than-appealing proposition.
Many astronomers give up trying to decide what's best for them and buy more than one scope. While this may not be the best advice for beginners, newcomers might want to keep this in mind when making a purchasing decision. For example, if your first scope is an 80 mm refractor, you might balance things out by getting a 12" Dobsonian in a year or two. That way, you'd have both a light bucket and a planetary/double star scope.
Avoid any thoughts of astrophotography for now. You are going to have your hands full dealing with the scope itself. Trust me.
Finally, avoid "paralyis-by-analysis." If you spend more than an hour a day reading telescope catalogs, you are probably in this category. Just get something; you'll feel a lot better.

OK, Ed -- You still haven't answered the question:
Which one would you buy, if you could only get one?

[Beginning] - [Next Page - The Choice]

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Your First Telescope"Which one should I buy?"

Your First Telescope
"Which one should I buy?"