POLAR ALLIGNMENT FOR EQ1 & EQ2
90 80 70 60
50
Fig.a
30 0
4030
2010 0
unlock
90 60
In order for your telescope to track objects in the sky you have to
align your mount. This means tilting the head over so that it
points to the North (or South) celestial pole. For people in the
Northern Hemisphere this is rather easy as there is a bright star
very near the spot Polaris. For casual observing, rough polar
alignment is adequate. Make sure your equatorial mount is level
and the red dot finder is aligned with the telescope before
beginning.
unlock
Look up your latitude on a map, road maps are good for this
purpose. Now look at the side of your mount head, there you will
see a scale running from 0-90 degrees (Fig.a). Unlock the hinge
of the mount by gently pulling on the lock lever counterclockwise. At the bottom of the head is a screw that pushes on a
tongue under the hinge, changing the angle. Spin this until your
latitude is shown on the scale by the indicator pin, then lock the
hinge (Fig.a).
EQ1
EQ2
Big Dipper
Fig.b
"Pole Star" is less than one degree from the North Celestial
Pole (NCP). Because it is not exactly at the NCP, Polaris
appears to trace a small circle around it as the Earth rotates.
Polaris is offset from the NCP, toward Cassiopeia and away
from the end of the handle of the Big Dipper (Fig.b).
Polaris
EQ1: Unlock the DEC lock knob and rotate the telescope tube
until the pointer on the setting circle reads 90˚. Retighten
the DEC lock knob. Loosen the azimuth lock knob and
rotate the mount horizontally until the R.A. axis points
roughly at Polaris. Retighten the azimuth lock knob. Look
through the finderscope and centre Polaris on the
crosshairs by adjusting the azimuth and latitude settings
if a more accurate polar alignment is desired.
+NCP
Little Dipper
Cassiopeia
EQ2: Unlock the DEC lock knob and rotate the telescope tube until the pointer on the setting circle reads 90˚.
Retighten the DEC lock knob. At the top of the main shaft is a white line with "R""A" on either side of it.
Loosen the azimuth lock knob and rotate the mount until the white line points roughly at Polaris. Retighten
the azimuth lock knob. Look through the finderscope and centre Polaris on the crosshairs by adjusting the
azimuth and latitude settings if a more accurate polar alignment is desired.
After a while you will notice your target drifting slowly North or
South depending on the direction of the pole relative to Polaris.
To keep the target in the center of the view, turn only the R.A.
slow-motion cable. After your telescope is polar aligned, 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 in order to keep an object in the field.
In the Southern Hemisphere you must align the mount to the
SCP by locating it's position with star patterns, without the
convenience of a nearby bright star. The closest star is the faint
5.5-mag. Sigma Octanis which is about one degree away. Two
sets of pointers which help to locate the SCP are alpha and
beta Crucis (in the Southern Cross) and a pointer running at a
right angle to a line connecting alpha and beta Centauri (Fig.c).
a
eg is
om tan
Oc
Southern Hemisphere
Fig.c
SCP +
alpha
Centauri
beta
Centauri
beta
Crucis
alpha
Crucis
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