Meade NG70-SM, Инструкция по эксплуатации

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Know your observing site: If possible, know
the location where you will be observing. Pay
attention to holes in the ground and other
obstacles. Is it a location where wild
animals, such as skunks, snakes, etc.,
may appear? Are there viewing obstructions
such as tall trees, street lights, headlights
and so forth? The best locations are dark
locations, the darker the better. Deep space
objects are easiest to see under dark skies.
But it is still possible to observe even in
a city.
Surf the Web and visit your local library: The
internet contains a huge amount of
astronomical information, both for children
and adults. Check out astronomy books from
your library. Look for star charts—these are
available on a monthly basis in
Astronomy
and Sky and Telescope magazines.
HAVE A GOOD TIME,
ASTRONOMY IS FUN!
SPECIFICATIONS
Optical tube focal length . . . . . . . . . 700mm
Objective lens diameter . . . . . . 70mm (2.8")
Focal ratio . . . . . . . . . . . . . . . . . . . . . . . . f/10
Mounting type . . . . . . . . . . . . . . . Altazimuth
What do the specifications mean?
Optical tube focal length is simply a
measurement of the length of the optical
tube. In other words, this is the distance
light travels in the telescope before being
brought to focus in you eyepiece. Your tube is
700mm long.
Objective lens diameter is how big the
lens is on your scope. Telescopes are
always described by how large their
objective lens is. Your telescope is 70mm
or 2.8 inches. Other telescopes are 90mm,
8 inches, 16 inches, or even 3 feet in
diameter. The Hubble Telescope’s objective
lens has a diameter of 2.4 meters (that’s
7.8 feet across!).
The focal ratio helps determine how fast the
photographic speed of a telescope is. The
lower the focal ratio number, the faster the
exposure. f/5 is faster than f/10. The faster
ASTRONOMY RESOURCES
• The Meade 4M Community
27 Hubble, Irvine, CA 92618
• Astronomical League
Executive Secretary
5675 Real del Norte, Las Cruces, NM 88012
• The Astronomical Society of the Pacific
390 Ashton Avenue, San Francisco, CA 94112
• The Planetary Society
65 North Catalina Avenue, Pasadena, CA 91106
• International Dark-Sky Association, Inc.
3225 N. First Avenue, Tucson, AZ 85719-2103
the ratio, the faster exposure time is
needed when a camera is hooked up to
the telescope. Your telescope has
slower focal ratio at f/10.
Sometimes, astronomers use focal reducers
to make slow exposure telescopes have
faster focal ratios.
Altaz mounting simply means your telescope
moves up and down (altitude or “alt”), and
side to side, (azimuth or “az”). Other
mounting configurations are available for
other telescopes, such as equatorial
mounting.
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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.
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