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note about astro-imaging
The SkyQuest XX14i IntelliScope Truss Tube Dobsonian is
designed for visual, not imaging, use. The Dobsonian mount
is not an equatorial-type mount, and is not motor driven for
long exposure astro-imaging. The telescope has also been
optically optimized for visual use, since photographic optimi-
zation degrades visual performance.
With that in mind, however, it is possible to do some simple
astro-imaging with the XX14i. With the use of afocal imaging
techniques (where the camera is simply held to the eyepiece
to take a picture) and digital cameras, it is possible to capture
images of bright objects. Certain imaging accessories, such
as the Orion SteadyPix, can help in obtaining images by the
afocal method.
6. Care and Maintenance
If you give your telescope reasonable care, it will last a life-
time. Store it in a clean, dry, dust-free place, safe from rapid
changes in temperature and humidity. Do not store the tele-
scope outdoors, although storage in a garage or shed is okay.
The telescope can be stored assembled or disassembled, but
be sure to keep the dust covers on the telescope when not
in use. We highly recommend storing the optical tube sec-
tions in the optional case set for the XX14i. Small components
like eyepieces and other accessories should be kept in an
optional accessory case.
Your XX14i requires very little mechanical maintenance. The
optical tube is steel and has a painted finish that is fairly
scratch-resistant. If a scratch does appear on the tube, it will
not harm the telescope. Smudges on the tube or base can be
wiped off with a soft cloth and household cleaning fluid.
Cleaning Eyepiece Lenses
Any quality optical lens cleaning tissue and optical lens clean-
ing fluid specifically designed for multi-coated optics can be
used to clean the exposed lenses of your eyepieces or find-
er scope. Never use regular glass cleaner or cleaning fluid
designed for eyeglasses. Before cleaning with fluid and tissue,
however, blow any loose particles off the lens with a blower
bulb or compressed air. Then apply some cleaning fluid to a
tissue, never directly on the optics. Wipe the lens gently in
a circular motion, then remove any excess fluid with a fresh
lens tissue. Oily fingerprints and smudges may be removed
using this method. Use caution; rubbing too hard may scratch
the lens. For larger lenses, clean only a small area at a time
using a fresh lens tissue on each area. Never reuse cleaning
tissues.
Cleaning Mirrors
You should not have to clean the telescope’s mirrors very
often; normally once every few years or so. Covering the tele-
scope with the dust covers when it is not in use will prevent
dust from accumulating on the mirrors. Improper cleaning can
scratch mirror coatings, so the fewer times you have to clean
the mirrors, the better. Small specks of dust or debris have
virtually no adverse effect on the visual performance of the
telescope. The large primary mirror and the elliptical second-
ary mirror of your telescope are front surface aluminized and
over-coated with hard silicon dioxide, which prevents the alu-
minum from oxidizing. These coatings normally last through
many years of use before requiring re-coating.
To clean the secondary mirror, you will need to remove it from
the telescope. Before doing so, remove the upper tube section
from the assembled telescope. Hold the secondary mirror sta-
tionary while loosening the center Phillips-head screw. Handle
the mirror by its edge; avoid touching the mirror surface itself.
Once the mirror (still in its holder) is removed from the tube,
follow the same procedure described below for cleaning the
primary mirror. You do not need to remove the secondary mir-
ror from its holder when cleaning.
To clean the primary mirror, first remove the rear end ring and
mirror cell from the lower tube section
(Figure 50a).
Loosen
the three hex head retaining bolts and carefully remove them
along with the two washers between the bolt head and mirror
surface
(Figure 50b)
and set them aside. You’ll notice that
there is a third, smaller washer underneath the large plastic
Figure 50.
(a)
The primary mirror is held in its cell with three hex head retaining bolts.
(b)
Between each bolt head and the mirror surface
are two washers, a metal washer and a plastic washer, which is the one that actually contacts the mirror surface. A third, smaller washer rests
directly on top of the threaded post that the retaining bolt screws into.
a.
b.
Small plastic
washer
(not visible)
Metal washer
Plastic washer