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7
piece. Alignment of the EZ Finder II is easiest during daylight,
before observing at night. Aim the telescope at a distant object
such as a telephone pole or roof chimney and center it in the
telescope’s eyepiece. The object should be at least 1/4 mile away.
Now, with the EZ Finder turned on, look though the EZ Finder II.
The object will appear in the eld of view near the red dot.
Note: The image in the telescope will appear upside-down
(rotated 180°). This is normal for reector telescopes (Figure 8).
Without moving the telescope, use the reex sight’s azimuth (left/
right) and altitude (up/down) adjustment knobs to position the
red dot on the object in the eyepiece.
When the red dot is centered on the distant object, check to make
sure the object is still centered in the telescope’s eld of view. If not,
re-center it and adjust the reex sight’s alignment again. When the
object is centered in the eyepiece and on the reex sight’s red dot,
the EZ Finder II is properly aligned with the telescope.
The reex sight’s alignment should be checked before every
observing session. Choose any bright star or planet, center the
object in the telescope’s eyepiece, then adjust the knobs until the
object is centered on the red dot of the EZ Finder II.
5. Setting Up 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 (Figure 1b) is designed to compen-
sate for that motion, allowing you to easily “track” the movement
of astronomical objects, thereby keeping them from drifting out of
the telescope’s eld 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
rst 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
axis out into space. Stars in the Northern Hemisphere appear
to revolve around the NCP.
To nd Polaris in the sky, look north and locate the pattern of the
Big Dipper (Figure 9). The two stars at the end of the “bowl” of
the Big Dipper point right to Polaris.
Observers in the Southern Hemisphere aren’t so fortunate to
have a bright star so near the south celestial pole (SCP). The
star Sigma Octantis lies about 1° from the SCP, but it is barely
visible with the naked eye (magnitude 5.5).
To polar align the StarBlast II 4.5 EQ:
1. Level the equatorial mount by adjusting the length of the
three tripod legs.
2. Loosen the latitude lock T-bolt. Turn the latitude adjust-
ment T-bolt until the pointer on the latitude scale is indicat-
ing the latitude of your observing site. If you don’t know
your latitude, consult a geographical atlas to nd it. For
example, if your latitude is 35° North, set the pointer to 35.
Then retighten the latitude lock T-bolt. The latitude setting
should not have to be adjusted again unless you move to a
different viewing location some distance away.
3. Loosen the Dec. lock knob and rotate the telescope optical
tube until it is parallel with the R.A. axis, as it is in Figure
1a. The pointer on the Dec. setting circle should read 90°.
Retighten the Dec. lock lever.
4. Loosen the azimuth lock knob at the base of the equa-
torial mount and rotate the mount so the telescope tube
(and R.A. axis) points roughly at Polaris. If you cannot see
Polaris directly from your observing site, consult a com-
pass and rotate the mount so the telescope points North.
Retighten the azimuth lock knob.
The equatorial mount is now polar aligned. From this point on in
your observing session, you should not make any further adjust-
ments to the azimuth or the latitude of the mount, nor should
you move the tripod. Doing so will undo the polar alignment. The
telescope should be moved only about its R.A. and Dec. axes.
Use of the R.A. and Dec. Slow-Motion Control
Cables
The R.A. and Dec. slow-motion control cables allow ne adjust-
ment of the telescope’s position to center objects within the eld
of view. Before you can use the cables, you must manually “slew”
the mount to point the telescope in the vicinity of the desired tar-
get. Do this by loosening the R.A. and Dec. lock knobs and mov-
ing the telescope about the mount’s R.A. and Dec. axes. Once
the telescope is pointed somewhere close to the object to be
viewed, retighten the mount’s R.A. and Dec. lock knobs.
The object should now be visible somewhere in the EZ Finder
II. If it isn’t, use the slow-motion controls to scan the surrounding
area of sky. When the object is visible in the EZ Finder II, use the
slow-motion controls to center the red dot on it. Now, look in the
Big Dipper
(in Ursa Major)
Little Dipper
(in Ursa Minor)
Cassiopeia
N.C.P.
Pointer
Stars
Polaris
Figure 9. To nd Polaris in the night sky, look north and nd the
Big Dipper. Extend an imaginary line from the two "Pointer Stars"
in the bowl of the Big Dipper. Go about ve times the distance
between those stars and you'll reach Polaris, which lies within 1° of
the north celestial pole (NCP).
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