Observing With The Telescope - Meade 2080 Instruction Manual

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object; lock the R.A. lock onto -the object. Next, turn
the telescope in Declination to read the correct Declina-
tion of the object. If the procedure has been followed
carefully, and if the telescope was well-aligned with the
pole, the desired object should now be in the telescopic
field of a low-power eyepiece.
If you do not immediately see the object you are seeking,
try searching the adjacent sky area, using the R.A. and
Dec. slow-motion controls to scan the surrounding regio~.
Keep in mind that, with the 25mm eyepiece, -the field of
view of the Model 2080 is about ~o and the field of the
Model 2120 about 0.40. Because of its much wider field,
the viewfinder may be of significant assistance in locating
and centering objects, after the setting circles have been
used to locate the approximate position of the object.
Pinpoint application of the setting circles requires that
the telescope be precisely aligned with the pole. Refer
to the preceding section on "Precise Polar Alignment" for
further details.
The setting circles may also be utilized in the absence
of a power source for the motor drive. In this case, however,
it is necessary to manually reset to the R.A. of the object
you are observing just before going to to the next object.
OBSERVING WITH THE TELESCOPE
The Meade Models 2080 and 2120 Schmidt-Cassegrain Telescopes
permit an extremely wide array of serious observational oppor-
tunities. ~ven in normal city conditions, with all of the
related air and light pollution, there are a good many
interesting celestial objects to observe. But to be sure
there is no substitute for the clear, steady, dar~ skies
generally found only away from urban environments, or on
mountaintops: objects previously viewed only in the city
take on -added detail or are seen in wider extension, or
even become visible at all for the first time.
The amateur astronome.r is faced typically with two broadly
defined problems when vie~ing astronomical objects through
the Earth's atmosphere: first is the clarity, or trans~arency,
of the air, and secondly the steadiness of the air. Th1S
latter characteristic is often referred to as the quality
of "seeing." Amateur astronomers talk almost constantly
about the "seeing conditions," since, perhaps ironically,
even the clearest, darkest skies may be almost worthless
for serious observations if the air is not steady. This
steadiness of the atmosphere is most readily gauged by
observing the "twinkling" of the stars: rapid twinkling