Orion SkyQuest XX12g Instruction Manual page 28

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. On larger lenses, clean only a small area at a time,
using a fresh lens tissue on each area. Never reuse tissues.
Cleaning the Telescope's 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 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 mirrors, the better. Small specks of dust or flecks of paint
have virtually no adverse effect on the visual performance of
the telescope. The large primary mirror and the elliptical sec-
ondary 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, 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,
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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 mirrors, you'll need the following:
• A sink or tub big enough to hold the mirror
• Distilled water, 1 gallon
• Squeeze bottle (for XX14g mirror only)
• A little dishwashing liquid
• 100% isopropyl alcohol (optional)
• Cotton balls
• Soft towel
To clean the primary mirror, you must carefully remove the
end ring and mirror support assembly from the telescope. To
do this remove the screws on the side of the tube near the rear
end ring. You do not need to remove the collimation screws on
the bottom of the mirror cell. Remove the entire end ring and
mirror cell assembly (including mirror) from the tube.
The primary mirrors and mirror support cells for the XX12g
and XX14g are quite different. The XX12g uses a flat-back
primary mirror and a 9-point floatation mirror cell, whereas
the XX14g uses a low mass, convex-back primary mirror and
a mirror cell that holds the mirror only in the center area.
Cleaning the XX12g Primary Mirror
1. The primary mirror is held down with clips, each one
fastened by two screws. Loosen the screws and remove
the clips. Then carefully remove the mirror from the mir-
ror cell. Do not touch the surface of the mirror with your
fingers; lift it carefully by the uncoated sides.
2. Set the mirror, aluminized face up, on a clean, soft towel.
3. Fill a clean sink or tub – not a bath tub but rather a small-
er plastic tub or bin – with room-temperature water, a few
drops of liquid dishwashing detergent, and if possible a
capful of 100% isopropyl alcohol.