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• Hazy skies, fog, and mist can also make it difficult to
focus when viewing terrestrially. The amount of detail seen
under these conditions is greatly reduced. Also, when
photographing under these conditions, the processed film
may come out a little grainier than normal with lower con-
trast and underexposed.
• If you wear corrective lenses (specifically glasses), you
may want to remove them when observing with an eye-
piece attached to the telescope. When using a camera,
however, you should always wear corrective lenses to
ensure the sharpest possible focus. If you have astigma-
tism, corrective lenses must be worn at all times.
Celestial Observing
With your telescope set up, you are ready to use it for observ-
ing. This section covers visual observing hints for both solar
system and deep sky objects as well as general observing
conditions which will affect your ability to observe.
Observing the Moon
Often, it is tempt-
ing to look at the
Moon when it is
full. At this time,
the face we see
is fully illuminated
and its light can
be overpowering.
In addition, little
or no contrast
can be seen dur-
ing this phase.
One of the best
times to observe the Moon is during its partial phases (around
the time of first or third quarter). Long shadows reveal a great
amount of detail on the lunar surface. At low power you will
be able to see most of the lunar disk at one time. Change to
higher power (magnification) to focus in on a smaller area.
Choose the lunar tracking rate from the StarSeeker’s MENU
tracking rate options to keep the moon centered in the eye-
piece even at high magnifications.
Lunar Observing Hints
• To increase contrast and bring out detail on the lunar surface,
use eyepiece filters. A yellow filter works well at improving
contrast while a neutral density or polarizing filter will reduce
overall surface brightness and glare.
Observing the Planets
Other fascinating targets include the five naked eye planets.
You can see Venus go through its lunar-like phases. Mars can
reveal a host of surface detail and one, if not both, of its polar
caps. You will be able to see the cloud belts of Jupiter and the
great Red Spot (if it is visible at the time you are observing).
In addition, you will also be able to see the moons of Jupiter
as they orbit the giant planet. Saturn, with its beautiful rings, is
easily visible at moderate power.
Planetary
Observing
Hints
• Remember that
atmospheric con-
ditions are usually
the limiting fac-
tor on how much
planetary detail
will be visible. So,
avoid observing
the planets when
they are low on
the horizon or when they are directly over a source of radi-
ating heat, such as a rooftop or chimney. See the “Seeing
Conditions” section later in this section.
• To increase contrast and bring out detail on the planetary
surface, try using color eyepiece filters.
Observing the Sun
Although overlooked by many amateur astronomers, solar
observation is both rewarding and fun. However, because
the Sun is so bright, special precautions must be taken when
observing our star so as not to damage your eyes or your
telescope.
Never project an image of the Sun through the telescope.
Tremendous heat build-up may result inside the optical tube.
This can damage the telescope and/or any accessories
attached to the telescope.
For safe solar viewing, use a solar filter that reduces the
intensity of the Sun’s light, making it safe to view. With a filter
you can see sunspots as they move across the solar disk and
faculae, which are bright patches seen near the Sun’s edge.
Solar Observing Hints
• The best time to observe the Sun is in the early morning
or late afternoon when the air is cooler.
• To center the Sun without looking into the eyepiece,
watch the shadow of the telescope tube until it forms a
circular shadow.
• To ensure accurate tracking, be sure to select solar
tracking rate.
Observing Deep Sky Objects
Deep sky objects are simply those objects outside the bound-
aries of our solar system. They include star clusters, planetary
nebulae, diffuse nebulae, double stars and other galaxies out-
side our own Milky Way. Most deep sky objects have a large
angular size. Therefore, low-to-moderate power is all you
need to see them. Visually, they are too faint to reveal any of
the color seen in long exposure photographs. Instead, they
appear black and white. And, because of their low surface
brightness, they should be observed from a dark sky location.
Light pollution around large urban areas washes out most
nebulae making them difficult, if not impossible, to observe.
Light Pollution Reduction filters help reduce the background
sky brightness, thus increasing contrast.