Meade TELESTAR RB-70, Инструкция по эксплуатации

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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.
If you use your Barlow lens with one of your
eyepieces, it doubles the magnification of
your eyepiece. Other types of Barlows can
triple or further increase the power of an
eyepiece. To find out how much your
magnification is when you use a Barlow,
multiply your eyepiece’s magnification
by two.
Eyepiece’s magnification x 2
=
Magnification with a 2X Barlow lens
Your 25mm low-power eyepiece magnifies
an object 28 times. Multiply 28 by 2 and you
get 56 times magnification with your Barlow.
It’s 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!
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:
12
• 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.
• When absolutely necessary, dust on the
front lens should be removed with very
gentle strokes of a camel hair brush or
blown off with an ear syringe (available at
most pharmacies).
• Fingerprints and organic materials on the
front lens may be removed with a solution
of 3 parts distilled water to 1 part
isopropyl alcohol. You may also add 1 drop
of biodegradable dishwashing soap per
pint of solution. Use soft, white facial
tissues and make short, gentle strokes.
Change tissues often.
CAUTION : Do not use scented or lotioned
tissues or damage could result to the optics.
DO NOT use a commercial photographic
lens cleaner.
OPTIONAL ACCESSORIES
#928 45° Erecting Prism (1.25 O.D.):
Correctly orients the telescopic image
during terrestrial observing and yields an
image position at a 45° angle to the main
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