5
2. Loosen the latitude lock knob a half turn or so (
Figure 10
).
3. Using the two latitude adjustment T-bolts, set the latitude so
that the pointer on the latitude scale indicates the latitude
of your observing location. (Loosen one latitude adjustment
T-bolt before tightening the other.) If you don’t know your
location’s latitude, you can look it up on the internet. For
example, if your latitude is 35° North, set the pointer to 35.
Then retighten the latitude lock knob. The latitude setting
should not have to be adjusted again unless you move to a
different viewing location some distance away.
4. Next, loosen the mount attachment knob (see Figure 10) just
enough to allow you to rotate the mount in azimuth. Then
rotate the mount by hand so the R.A. axis points rough-
ly at Polaris (
Figure 6
). If you cannot see Polaris directly
from your observing site, consult a compass and rotate the
mount so the telescope points North. Then retighten the
mount attachment knob.
The equatorial mount is now (roughly) polar aligned. From
this point on in your observing session, you should not
make any further adjustments to the azimuth or the lati-
tude of the mount, nor should you move the tripod. Doing
so will ruin the polar alignment. The telescope should
henceforth be moved only about its R.A. and Dec. axes.
Figure 7. A
) Balance a telescope in right ascension by sliding the counterweight along the shaft until it counterbalances the telescope.
B
)
Balance the telescope on the declination axis by sliding the dovetail mounting bar forward or back in the mount’s saddle.
A.
B.
R.A. lock knob
Saddle
clamp
knobs
Counterweight lock
knob
Counterweight
shaft
Dec. lock knob
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).
Big Dipper
(in Ursa Major)
Little Dipper
(in Ursa Minor)
Cassiopeia
N.C.P.
Pointer
Stars
Polaris
