APM SK P25012EQ6-2IN, Инструкция по эксплуатации

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11
T
racking celestial objects
When observing through a telescope, astronomical objects
appear to move slowly through the telescope's field of view.
When the mount is correctly polar aligned, and the motors
are on, the R.A. motor will start rotating the mount to track
objects as they move through the field. The rotation speed of
the R.A. drive matches the Earth's rotation rate for stars to
appear stationary in the telescope eyepiece. No further
adjustments in the azimuth and latitude of the mount should
be made in the observing session, nor should you move the
tripod. Only movements in R.A. and DEC axis should be
made. The DEC. motion control is very useful for doing
astrophotography but not needed for tracking.
The polar alignment is now complete. This should get the
mount's R.A. axis within 5 arc-minutes of the celestial pole.
Due to its proper motion, Polaris can be seen to move with
respect to the Pole from year to year. The tick marks in the
Polarscope can be used to compensate for this motion.
Fig.h-5 can be used to determine the current position of
Polaris along the line in the polarscope.
Using the Polarscope in the Sorthern Hemisphere
There is a 4-star pattern in the polar scope, which resembles
the bucket of the Big Dipper. In the Southern Hemisphere,
there is an Asterism in Octans, which has this shape. By
rotating the R.A. axis and by adjusting the altitude and
azimuth of the mount, the four stars in the Asterism can be
placed in the circles in the Pole Finder (Fig.h-6). This
procedure can be somewhat difficult in the city because all
four of these stars are fainter than Magnitude 5.
Year
2000
2002
2004
2006
2008
2010
2012
2014
2016
2018
2020
Distance
45'
44'
44'
43'
43'
42'
42'
41'
40'
40'
39'
Upsilon (
ν
)
Chi (
χ
)
Sigma (
σ
)
Tau (
τ
)
Octans
40'
60'
Point this line at
Beta-Ursa Minoris
Place Polaris here
Fig.h-4
Fig.h-5
Fig.h-6