ORION TELESCOPES & BINOCULARS ShortTube 4.5 EQ 9849 Instruction Manual Download

Page: 14 / 16

E. Deep-Sky Objects

Under dark skies, you can observe a wealth of fascinating
deep-sky objects, including gaseous nebulas, open and
globular star clusters, and a variety of different types of
galaxies. Most deep-sky objects are very faint, so it is impor-
tant that you find an observing site well away from light pollu-
tion. Take plenty of time to let your eyes adjust to the dark-
ness. Do not expect these subjects to appear like the
photographs you see in books and magazines; most will look
like dim gray smudges. Our eyes are not sensitive enough to
see color in deep-sky objects except in a few of the brightest
ones. But as you become more experienced and your
observing skills get sharper, you will be able to ferret out
more and more subtle details and structure.

8. 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 OK.
Small components like eyepieces and other accessories
should be kept in a protective box or storage case. Keep the
dust cover on the front of the telescope when not in use.

Your ShortTube 4.5 EQ requires very little mechanical main-
tenance. The optical tube has a smooth painted finish that is
fairly scratch-resistant. If a scratch does appear on the tube, it
will not harm the telescope. If you wish, you may apply some
auto touch-up paint to the scratch. Smudges on the tube can
be wiped off with a soft cloth and a household cleaner.

Cleaning Eyepieces

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. Never use
regular glass cleaner or cleaning fluid designed for eyeglasses

Before cleaning with fluid and tissue, blow any loose parti-
cles 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. On larger lenses,
clean only a small area at a time, using a fresh lens tissue
on each area. Never reuse tissues

Cleaning Mirrors

You should not have to clean the telescope’s mirrors very
often; normally once every year or so. Covering the telescope
with the dust cover 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 mir-
rors, the better. Small specks of dust or flecks of paint have
virtually no effect on the visual performance of the telescope.

The large primary mirror and the elliptical secondary mirror of
your telescope are front-surface aluminized and over-coated
with hard silicon dioxide, which prevents the aluminum from

oxidizing. These coatings normally last through many years of
use before requiring re-coating (which is easily done).

To clean the secondary mirror, first remove it from the tele-
scope. Do this by holding the secondary mirror holder stationary
while turning the center Phillips-head screw. Be careful, there is
a spring between the secondary mirror holder and the Phillips
head screw; be sure that it will not fall into the optical tube and
hit the primary mirror. Now, remove the secondary mirror from
its holder by removing the securing clip. This is done by
unthreading the screw that connects the clip to the mirror hold-
er. Carefully handle the secondary mirror by its edges only. Do
not touch the mirror surface. Then follow the same procedure
described below for cleaning the primary mirror.

To clean the primary mirror, first carefully remove the mirror
cell from the telescope. For the ShortTube 4.5 EQ, this
means you must remove the three screws on the edge of the
mirror cell. You will notice the primary mirror is held in the
mirror cell with three clips held by two screws each. Loosen
the screws and remove the clips.

You may now remove the mirror from the mirror cell. Do not
touch the surface of the mirror with your fingers. Lift the mir-
ror carefully by the edges. Set the mirror in a clean soft
towel. Fill a clean sink free of abrasive cleanser, with room-
temperature water, a few drops of liquid dishwashing deter-
gent, and if possible, a capfull of rubbing alcohol. Submerge
the mirror (aluminized face up) in the water and let it soak for
a few minutes (or hours if it’s a very dirty mirror). Wipe the
mirror under water with clean cotton balls, using extremely
light pressure and stroking in straight line across the mirror.
Use one ball for each wipe across the mirror. Then rinse the
mirror under a stream of lukewarm water. Any particles on
the surface can be swabbed gently with a series of cotton
balls, each used just one time. Dry the mirror in a stream of
air (a “blower bulb” works great), or remove any stray drops
of water with the corner of a paper towel. Water will run off a
clean surface. Cover the mirror surface with Kleenex, and
leave the mirror in a warm area until it is completely dry
before replacing it in the mirror cell and telescope.