Orion 8 EQ - Manual (Page 8)

8
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).
For general visual observation, an approximate polar align-
ment is sufficient.
1. Level the equatorial mount by adjusting the length of the
three tripod legs.
2. There are two latitude adjusting L-bolts (see Figure 7);
loosen one while tightening the other. By doing this you will
adjust the latitude of the mount. Continue adjusting the
mount until the pointer on the latitude scale is set at the lat-
itude of your observing site. If you don’t know your latitude,
consult a geographical atlas to find it. For example, if your
latitude is 35° North, set the pointer to 35. The latitude set-
ting should not have to be adjusted again unless you move
to a different viewing location some distance away.
3. Loosen the Dec. lock lever and rotate the telescope’s opti-
cal tube until it is parallel with the right ascension axis, as
it is in Figure 7.
4. Move the tripod so the telescope tube and right ascension
axis point roughly at Polaris. If you cannot see Polaris
directly from your observing site, consult a compass and
rotate the tripod so the telescope points north. There is a
label bearing a large “N” at the base of the equatorial
mount (Figure 9). It should be facing north.
The equatorial mount is now polar aligned for casual observ-
ing. More precise polar alignment is recommended for
astrophotography. For this we suggest using the optional polar
axis finder scope.
From this point on in your observing session, you should not
make any further adjustments to the latitude of the mount, nor
should you move the tripod. Doing so will undo the polar align-
ment. The telescope should be moved only about its R.A. and
Dec. axes.
Polar Alignment Using the Optional Polar Axis
Finder Scope
The SkyView Pro EQ mount can be equipped with an optional
polar axis finder scope (Figure 10a) which goes inside the
right ascension axis of the mount. It makes accurate polar
alignment quick and easy to do.
To install the polar axis finder scope, remove the cover at the
rear of the mount’s right ascension axis and thread the polar
axis finder scope into the equatorial mount until tight (Figure
10b).
Figure 9. For polar alignment, position the tripod so that the "N"
label at the base of the mount faces north. The azimuth fine
adjustment knobs above it are used to make small adjustments to the
mount’s azimuth position. Be certain to loosen the tripod attachment
knob on the central support shaft before adjusting these knobs.
Azimuth
adjustment
knobs
Figure 10a. The optional polar axis finder scope.
Eyepiece
focus ring
Focus lock
ring
Objective
lens
Figure 10b. Installing the optional polar axis finder scope.
Big Dipper
(in Ursa Major)
Little Dipper
(in Ursa Minor)
Cassiopeia
N.C.P.
Poin
ter
Stars
Polaris
Figure 8. To find Polaris in the night sky, look north and find the
Big Dipper. Extend an imaginary line from the two "Pointer Stars" in
the bowl of the Big Dipper. Go about five times the distance
between those stars and you'll reach Polaris, which lies within 1° of
the north celestial pole (NCP).