8
ring clamp knob a few turns, until you can slide the tele-
scope tube forward and back inside the ring. Using a slight
twisting motion on the optical tube can help move the tube
within the ring.
6. Position the telescope so it remains horizontal when you
carefully let go with both hands. This is the balance point.
Before clamping the tube ring tight again, rotate the tele-
scope so the eyepiece is at a convenient angle for view-
ing. When you are actually observing with the telescope,
you can adjust the eyepiece position by loosening the tube
ring and rotating the optical tube.
7. Retighten the tube ring clamp knobs.
The telescope is now balanced on both axes. Now when you
loosen the lock knob on one or both axes and manually point
the telescope, it should move without resistance and should
not drift from where you point it.
4. Understanding and Using
the Equatorial Mount
When you look at the night sky, you no doubt have noticed
the stars appear to move slowly from east to west over time.
That apparent motion is caused by the Earth’s rotation (from
west to east). An equatorial mount is designed to compensate
for that motion, allowing you to easily “track” the movement of
astronomical objects, thereby keeping them from drifting out
of the telescope’s field of view while you’re observing.
This is accomplished by slowly rotating the telescope on its
right ascension (R.A.) axis, using only the R.A. slow-motion
cable. But first the R.A. axis of the mount must be aligned
with the Earth’s rotational (polar) axis—a process called polar
alignment.
Polar Alignment
For Northern Hemisphere observers, approximate polar align-
ment is achieved by pointing the mount’s right ascension axis
at the North Star (Polaris). It lies within 1° of the north celes-
tial pole (NCP), which is an extension of the Earth’s rotational
Figure
17
.
Eyepiece is shown installed in the focuser.
Figure
19
.
Get to know the knobs and setting circles on the
equatorial mount.
Thumbscrew
Focuser
Dec. lock
knob
Dec. setting
circle
R.A. setting
circle
R.A. lock
knob
Focus
wheel
Eyepiece
Figure 18.
The red dot finder scope has vertical and (inset)
horizontal adjustment knobs for aligning it with the telescope.
Power switch
Plastic
tab
Vertical knob
Horizontal knob
Opposite side
Latitude
adjustment bolt
Latitude
lock
knob