21
ror clip anchor screws and remove the clips. Next, hold the
mirror by its edge, and remove it from the mirror cell. Be care-
ful not to touch the aluminized surface of the mirror with your
fingers. Set the mirror on a clean, soft towel.
Fill a clean sink, free of abrasive cleanser, with room-temper-
ature water, a few drops of liquid dishwashing detergent, and
if possible, a cap-full of rubbing alcohol. Submerge the mirror
(aluminized face up) in the water and let it soak for several
minutes (or hours if it is a very dirty mirror). Wipe the mirror
underwater with clean cotton balls, using extremely light pres-
sure and stroking in straight lines across the surface. Use one
ball for each wipe across the mirror. Then rinse the mirror
under a stream of lukewarm water. Any particles on the sur-
face can be swabbed gently with a series of clean 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. Dry the bottom and the edges with a towel (not the mirror
surface!). Leave the entire assembly in a warm area until it is
completely dry before replacing it in the mirror cell. Then rein-
stall the mirror cell in the telescope optical tube with the screws.
To minimize the need to clean your telescope, replace all lens
covers once you have finished using it. This will prevent con-
taminants from entering the optical tube.
Collimation
Collimation is the process of adjusting the telescope’s mirrors
so they are aligned with one another. Your telescope’s optics
were aligned at the factory, and should not need much adjust-
ment unless the telescope was jarred while in transit. Accurate
mirror alignment is important to ensure the peak performance
of your telescope, so it should be checked regularly. Collima-
tion is a relatively easy process and can be done in daylight or
darkness.
To check collimation, remove the eyepiece and look down the
focuser drawtube. You should see the secondary mirror cen-
tered in the drawtube, as well as the reflection of the primary
mirror centered in the secondary mirror, and the reflection of
the secondary mirror (and your eye) centered in the reflection
of the primary mirror, as in
Figure 12a. If anything is off-center,
proceed with the following collimating procedure.
The Collimation Cap
Your StarSeeker 130 II comes with a “quick collimation cap”
(
Figure 13). This is a simple cap that fits on the focuser draw-
tube like a dust cap, but has a tiny hole in the center and a
reflective inner surface. The collimation cap helps center your
eye over the focuser drawtube so that aligning the optical com-
ponents is easier to achieve. The reflective surface provides a
distinct visual reference that is helpful in centering the mirror
reflections
. Figures 12b through 12d assume that you have
the collimation cap in place.
The Primary Mirror Center Mark
You’ll notice that the primary mirror of the StarSeeker has a
tiny ring (sticker) marking its center (
Figure 14). This “center
mark” allows you to achieve a very precise collimation; you
don’t have to guess where the exact center of the mirror is.
NOTE: The center ring sticker need not ever be removed
from the primary mirror. Because it lies directly in the
shadow of the secondary mirror, its presence in no way
adversely affects the optical performance of the tele-
scope or the image quality. That might seem counter-
intuitive, but it’s true!
Preparing the Telescope for Collimation
Once you get the hang of collimating, you will be able to do it
quickly even in the dark. For now, it is best to collimate in day-
light, preferably in a brightly lit room and aimed at a white wall.
It is recommended that the telescope tube be oriented hori-
zontally. This will prevent any parts from the secondary mirror
from falling down onto the primary mirror and causing damage
if something comes loose while you are making adjustments.
Figure 13.
The quick collimation cap, which features an
inner reflective surface, helps in centering reflections of the
optics in the focuser during the collimation process.
Figure 14.
The tiny adhesive ring in the exact center of the
primary mirror should not be removed!
Summary of Contents for 8993
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