23
north star) is a good star to use for star testing, because it will
not move out of the field of view.
note about the 2" Crayford Focuser
The 2" Crayford focuser of the XX14i can be collimated using
three pairs of push-pull screws located at the base of the fo-
cuser. The focuser was collimated at the factory, however, and
should not need to be adjusted. Focuser collimating is only
required under very rare circumstances, but has been made
available for this telescope should such a need arise.
4. Using Your Telescope
Before using your SkyQuest telescope for the first time at
night, we recommend getting a feel for its basic functions dur-
ing daylight hours. Find a spot outdoors where you have a
clear view of some object or landmark 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 pavement to
ensure smooth movement of the telescope.
Remember, never point the telescope at or near the Sun with-
out using a proper solar filter over the front aperture.
altitude and azimuth Motion
The XX14i’s Dobsonian base permits smooth motion of the
telescope along two axes: altitude (up/down) and azimuth
(left/right)
(Figure 42).
For altitude motion, the side bearings
(made of heavy duty ABS plastic) on the telescope tube glide
on pairs of bearing cylinders made from ultra-high molecular
weight (UHMW) polyethylene. For azimuth motion, the Ebony
Star laminate on the underside of the top baseplate rides on
three Virgin Teflon bearing pads attached to the ground base-
plate. These choices of bearing materials provide optimum
friction characteristics for moving the telescope when slewing
or tracking.
To move the telescope, simply take hold of the navigation
knob (black knob on upper tube section) and gently move the
tube up or down and left or right as desired. Both motions can
be made simultaneously and in a continuous manner for easy
aiming.
When the telescope is pointed high in altitude, rotating the
tube in azimuth can cause the base to “tip” because of the
reduced leverage. In this case it is helpful to place your other
hand on the base or the optical tube to help “guide” the tube.
Setting the altitude Tension
A nice feature of the SkyQuest IntelliScope Dobsonians is the
redesigned CorrecTension system. Because of their relatively
light weight, smaller Dobsonians (under 16") have always
been plagued by insufficient friction on the altitude bearing
surfaces. As a result, such telescopes move up and down
much too freely. This causes problems when the observer
tries to accurately center and track an object for viewing,
especially at higher powers. Also, the telescope becomes
very sensitive to balance. SkyQuest IntelliScope Dobsonians
employ a simple yet effective remedy for the friction problem.
CorrecTension Friction Optimization utilizes a simple “disc
brake” to apply the correct level of tension to the altitude bear-
ings. With this system, you can change eyepieces or add a
barlow lens without having to tediously adjust the telescope’s
balance as you would with other Dobsonians.
The telescope should move smoothly with just gentle hand
pressure. While azimuth friction is not adjustable, the altitude
friction can be adjusted to the desired level by loosening or
tightening the altitude tensioning knob. Note that the altitude
tensioning knob is the knob on the same side of the base as
the IntelliScope Controller Port. The knob on the opposite side
of the base is merely an encoder retaining knob; it does not
affect altitude tension and should always be fully tightened.
A good way to set the altitude tension is to point the telescope
at about a 45° angle. Then, turn the altitude tensioning knob
until the altitude motion feels roughly equal to the azimuth
Figure 41.
A star test will determine if a telescope’s optics are
properly collimated. An unfocused view of a bright star through
the eyepiece should appear as illustrated on the right if the optics
are perfectly collimated. If the circle is unsymmetrical, as in the
illustration on the left, the telescope needs collimation.
Out of collimation
Collimated
Figure 42.
Dobsonians have two axes of motion; altitude (up/
down) and azimuth (left/right).
Altitude
Azimuth
