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Astronomy_Astrology_Telescopes
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Telescopes 101
Buying the right telescope to take
your love of astronomy to the next level is a big next
step in the development of your passion for the stars.
In many ways, it is a big step from someone who is just
fooling around with astronomy to a serious student of
the science. But you and I both know that there is still
another big step after buying a telescope before you
really know how to use it. So it is critically important
that you get just the right telescope for where you are
and what your star gazing preferences are. To start
with, let's discuss the three major kinds of telescopes
and then lay down some 典elescope 101・concepts to
increase your chances that you will buy the right thing.
The three primary types of telescopes that the amateur
astronomer might buy are the Refractor, the Reflector
and the Schmidt Cassegrain telescope. The first two are
named for the kind of lens that is used. It is pretty
easy to see that the lens is the heart of the telescope
so the kind that you will use will determine the success
of your use of that telescope. The refractor lens is the
simplest because it uses a convex lens to focus the
light on the eyepiece. So the lens bends outwards for
this purpose. The refractor telescope's strength is in
viewing planets. The reflector's strength is in seeing
more distant objects and the lens is concave or bends
in. It uses mirrors to focus the image that you
eventually see. The final type, the Schmidt Cassegrain
telescope is the most complex and accomplishes the goals
of both but it uses an involved system of mirrors to
capture the image you want to see. So to select just the
right kind of telescope, your objectives in using the
telescope are important. To really understand the
strengths and weaknesses not only of the lenses and
telescope design but also in how the telescope performs
in various star gazing situations, it is best to do some
homework up front and get exposure to the different
kinds. So before you make your first purchase・ * Above
all, establish a relationship with a reputable telescope
shop that employs people who know their stuff. If you
buy your telescope at a Wal-Mart or department store,
the odds you will get the right thing are remote. * Pick
the brains of the experts. If you are not already active
in an astronomy society or club, the sales people at the
telescope store will be able to guide you to the active
societies in your area. Once you have connections with
people who have bought telescopes, you can get advice
about what works and what to avoid that is more valid
than anything you will get from a web article or a
salesperson at Wal-Mart. * Try before you buy. This is
another advantage of going on some field trips with the
astronomy club. You can set aside some quality hours
with people who know telescopes and have their rigs set
up to examine their equipment, learn the key technical
aspects, and try them out before you sink money in your
own set up. There are other considerations to factor
into your final purchase decision. How mobile must your
telescope be? The tripod or other accessory decisions
will change significantly with a telescope that will
live on your deck versus one that you plan to take to
many remote locations. Along those lines, how difficult
is the set up and break down? How complex is the
telescope and will you have trouble with maintenance?
Network to get the answers to these and other questions.
If you do your homework like this, you will find just
the right telescope for this next big step in the
evolution of your passion for
astronomy.
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