Considering a First Telescope
Before making an investment in your first
telescope, we recommend learning a little about astronomy and
getting feedback from TAAA members. By attending a club star
party, you can observe through member scopes to get an idea of
what to expect. You do not need to own a telescope to come!
As a TAAA member,
you may also attend our Astronomy Fundamentals Special Interest
Group meetings held each month. These meetings provide an
opportunity to network with other amateur astronomers, learn more
about telescopes, as well as the basics of astronomy. |
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Question: |
How much
should I expect to spend on my first telescope? |
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Answer: |
An
investment of $500 is typical for an adequate first telescope. A
cheaper mass market scope typically causes more frustration
than it is worth. |
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Question: |
What is
better... a reflector or a refractor? |
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Answer: |
General
rule, refractors are EXPENSIVE to get good ones, reflectors are
less expensive and work very well, most amateur and almost all
professional scopes are reflectors for this very reason. Good
performance at lower cost. |
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Question: |
How much
power do I need? 200, 300, 500x? |
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Answer: |
If it
(the telescope) advertises power, walk away from it!!!!!
Magnification is not what you look at, it is aperture that counts.
Aperture is diameter of the main lens or mirror. measured in
inches or millimeters for small scopes. I typically use between 60
and 150x for most of my observing, with higher magnification (more
than 250x) being only rarely usable, no matter how good the
telescope is. 150-250x is ideal for most planet viewing, anything
more is probably useless. |
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Question: |
I was
told that the problem with the refractor telescopes is that the
image is inverted, and the reflectors not. Is that a good reason
to choose the reflector telescope? |
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Answer: |
Whoever
told you that an inverted image is a problem doesn't know much
about telescopes, don't listen to them. All astronomical
telescopes (including mine) invert or reverse the image some way
and it really doesn't matter. There are accessories that will fix
this but we don't use them unless you also want to use the scope
for daylight objects (bird spotting or such) where a right-side-up
image matters. |
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Question: |
I was
thinking of getting an <XYZ> scope with the computer that will
find things for me. |
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Answer: |
Recently, many more telescopes are being equipped with computer "GOTO"
drives that allow the scope to automatically point to many objects
in the sky. Most of these work well, but they do take some
knowledge and patience to learn to use and I would not highly
recommend them to the beginner. These scopes are also very
expensive, often many thousands of dollars. If you are looking for
a first scope you should probably start simpler than this, maybe
step-up if you want to later. |
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A solid mount. If the mount is not stable your
image will jump about, particularly at high power. You should be
able to move from one point in the sky to another quickly and
smoothly. Fine motion controls are not necessary in most small
scopes.
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Do not take any notice of magnification claims;
it is aperture that counts. Aperture is the diameter of the main
mirror or lens of the scope. All scopes are referred to by their
aperture, from the smallest amateur scope to the largest
professional scopes on mountaintops.
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Six inches or more in aperture. With a six inch
it is possible to see any of the Messier objects and beyond. This
includes star clusters, nebulas, and dozens of galaxies. A scope of
this size should also give good views of the planets.
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A solid mount. This is the failing point in
most small scopes I see, if the mount is not good, the scope will
result in hours of frustration and little observing.
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At least an 1-1/4 inch focuser, this focuser
accepts the standard eyepieces that most amateurs use. Remember that
your eyepieces may represent a substantial investment over time, and
the 1-1/4 inch will be usable with any scope you buy in the future.
Cheap scopes use 0.956" eyepieces.
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A solid mount.
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For a first scope, a reflector is recommended
with a minimum of a six inch mirror. DO NOT get smaller than six inch with a
reflector, the smaller scopes are usually department store scopes and
are usually very cheap and nearly unusable. The Dobsonian telescope is
a design that has become popular amongst amateur astronomers because
it results in an extremely simple and rugged large-aperture instrument
at low cost.
The term "Dobsonian" or "Dob" refers to any
telescope with an alt-azimuth mount and a Newtonian telescope tube
assembly that feature several innovations made popular by John Dobson.
The telescope is a favorite among amateur telescope makers who
pioneered many of its original features and has been made increasingly
popular by commercial telescope makers. If you upgrade to a larger scope, or find out you
just don't use it, a good Dobsonian can be sold for most of what you
paid for it as they keep their value over time.
A six inch should cost about $350 new while an
eight inch will be closer to $500. Consider budget for accessories and
books. A Telrad (about $40) is an indispensable accessory for a
Dobsonian.
I would suggest you buy your telescope at a local
astronomy shop. You may pay a little more (retail price plus sales
tax) but a good store will offer assistance with your new scope,
showing you how to set it up and use it. A good store will often have
evening hours to allow just this sort of activity, often allowing you
use of a showroom model so you really know what you are getting and if
it will work for you. Here in Tucson,
Starizona
and Stellar Vision Astronomy offer excellent
customer service and evening "Try-It-Out" opportunities.
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