Focusing The Telescope; Using Your Telescope - Orion SKYQUEST XT10 CLASSIC Instruction Manual

Altitude
Azimuth
Figure 9.
The SkyQuest has two axes of motion: altitude (up/
down) and azimuth (left/right).
The CorrecTension system is now installed and engaged.
If you wish to remove the telescope from the base, you will
first need to disconnect the springs from the "posts" on the
Dobsonian base. The springs will remain captive on the alti-
tude side bearings, so they will not get lost.
inserting an Eyepiece
The final step in the assembly process is to insert an eyepiece
into the telescope's focuser. Take the cover cap off the end of
the focuser drawtube.
For the XT6: Loosen the two thumbscrews on the eyepiece
holder and insert the eyepiece. Then secure it in place with the
thumbscrews.
For the XT8 and XT10: There are three thumbscrews on
the focuser, one holds the eyepiece, and two hold the 1.25"
adapter. To insert the eyepiece, loosen the thumbscrew that is
on the 1.25" adapter itself (it will be highest up on the focuser).
Insert the eyepiece into the adapter and secure it by tighten-
ing the thumbscrew.
The assembly of your SkyQuest Dobsonian is now complete.
It should appear as in Figure 1. The dust cover on the front of
the telescope should always remain in place when the tele-
scope is not in use. It is also a good idea to store eyepieces in
an eyepiece case and to replace the cover cap on the focuser
when the telescope is idle.

3. using Your telescope

It is best to get a feel for the basic functions of the SkyQuest
Dobsonian during the day, before observing astronomical
objects at night. This way you will not have to fumble around
2" eyepiece adapter
Focus knobs
Figure 10.
The 2" Crayford focuser (XT8 and XT10)
trying to orient yourself in the dark! Find a spot outdoors
where you have plenty of room to move around the telescope,
and where you have a clear view of some object or vista that is
at least 1/4-mile away. It is not critical that the base be exactly
level, but it should be placed on somewhat flat ground or pave-
ment to ensure smooth movement of the telescope.
Remember, never point the telescope at or near the
Sun without using a proper solar filter over the front
aperture!
altitude and azimuth
The Dobsonian base of the SkyQuest permits motion of the
telescope along two axes: altitude (up/down) and azimuth
(left/right) (Figure 9). This is very convenient, since up/down
and left/right are the most "natural" ways that people aim. As a
result, pointing the telescope is exceptionally easy.
Simply take hold of the end of the tube and move it left or
right so the base rotates about its central azimuth bolt, and
move it up or down so the altitude side bearings rotate in the
base's cradle. Both motions can be made simultaneously and
in a continuous manner for easy aiming. Move the telescope
gently—let it glide. In this way you can point the telescope to
any position in the night sky, from horizon to horizon.

Focusing the telescope

Insert the 25mm eyepiece into the focuser and secure with the
thumbscrew(s). Move the telescope so the front (open) end is
pointing in the general direction of an object at least 1/4-mile
away. Now, with your fingers, slowly rotate one of the focusing
knobs until the object comes into sharp focus. Go a little bit
beyond sharp focus until the image just starts to blur again,
then reverse the rotation of the knob, just to make sure you've
hit the exact focus point.
If you have trouble focusing, rotate the focusing knob so the
drawtube is in as far as it will go. Now look through the eye-
piece while slowly rotating the focusing knob in the opposite
direction. You should soon see the point at which focus is
reached.
The 2" Crayford focuser of the XT8 and XT10 models features
a thumb screw on the bottom of the focuser body (Figure 10)
1.25" eyepiece
adapter
Focus lock
thumbscrew
Tension adjustment screw
7