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USE THE SPECIFICATIONS TO
CALCULATE THE MAGNIFICATION OF
YOUR EYEPIECE
The power of a telescope is how much
it magnifies objects. Your 25mm eyepiece
magnifies an object 28 times. Your 9mm
eyepiece magnifies objects 78 times.
But if you obtain other eyepieces, you can
calculate how much magnification they have
with your telescope. Just divide the focal
length of the telescope by the focal length of
the eyepiece.
Focal Length of the Telescope
÷
Focal Length of the Eyepiece
=
Magnification
Look at the specifications. You will see that
the focal length of your scope is 700mm.
Let’s say that you have obtained a 13mm
eyepiece. You can tell that what the focal
length of your eyepiece is as it is always
printed on the side of an eyepiece. Divide:
700 ÷ 13, which equals 53.8. Round this
off to the nearest whole number and your
new eyepiece magnifies objects 54 times.
Its worth repeating: Keep in mind that a
bright, clear, but smaller image is more
interesting than a larger, dimmer, fuzzy one.
Using too high a power eyepiece is one of
the most common mistakes made by new
astronomers. So don’t think that higher
magnification is necessarily better—quite
often the best view is with lower
magnification value!
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TAKING CARE OF YOUR TELESCOPE
Your telescope is a precision optical
instrument designed for a lifetime of
rewarding viewing. It will rarely, if ever,
require factory servicing or maintenance.
Follow these guidelines to keep your
telescope in the best condition:
• Avoid cleaning the telescope’s lenses. A
little dust on the front surface of the
telescope’s correcting lens will not cause
loss of image quality.
Looking at or near the Sun will cause irreversible damage to your eye. Do not point this telescope at or near the Sun. Do not look through the telescope as it is moving.
JOIN AN ASTRONOMY CLUB, ATTEND A STAR PARTY
One of the best ways to increase your knowledge of
astronomy is to join an astronomy club. Check your local
newspaper, school, library, or telescope dealer/ store to
find out if there’s a club in your area.
Many groups also hold regularly scheduled Star Parties
at which you can check out and observe with many
different telescopes and other pieces of astronomical
equipment. Magazines such as
Sky and Telescope
and
Astronomy
print schedules for many popular Star Parties
around the United States and Canada.
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