Sky-Watcher EQ2 MOUNT - Manual (Page 14)

14
F
ocusing
Fig.g
unlock
0
90 80 70 6050
4030 2010
EQ2 EQ1
Fig.h
Slowly turn the focus knobs under the focuser, one way or the other, until
the image in the eyepiece is sharp (Fig.g). The image usually has to be
finely refocused over time, due to small variations caused by temperature
changes, flexures, etc. This often happens with short focal ratio
telescopes, particularly when they haven't yet reached outside
temperature. Refocusing is almost always necessary when you change an
eyepiece or add or remove a Barlow lens.
EQ1:
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.
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. Unlock the hinge of the mount by gently
pulling on the lock lever counter-clockwise. 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.h).
"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.i).
Fig.i
P
olar Alignment
+
Polaris
Cassiopeia
Little Dipper
Big Dipper
NCP
0 30
60
90
unlock
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.
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.
EQ2:
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.