Orion 9536 Manual page 20

Figure 11.
The view of a collimated telescope as seen through
the focuser of the StarSeeker 114mm and 130mm reflectors.
and 130mm, however, have collimation screws that can be
used to adjust the alignment of the primary mirror.
To check if your telescope is in collimation refer to figure 6-1.
If you look into the eyepiece adapter (without an eyepiece) at
the top of the focuser, this is what you should see. If the reflec-
tion of your eye is off center, then collimating is necessary.
The StarSeeker 114mm and 130mm reflectors come with a
collimating cap. This is a simple cap that fits on the focuser
drawtube like a dust cap, but has a hole in the center and a
silver bottom. This helps center your eye so that collimating is
easy to perform.
In addition to the collimating cap, you'll notice a small ring
label on the exact center of the primary mirror. This "center
mark" allows you to achieve a very precise alignment of the
primary mirror; you don't have to guess where the center of
the mirror is. You simply adjust the primary mirror position
(described below) until the reflection of the hole in the col-
limating cap (the "dot") is centered inside the ring.
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!
Collimating the StarSeeker 114mm
Adjustments to the collimation of the telescope can be made
by turning the collimation adjustment knobs located at the
rear of the optical tube (Figure 12). First loosen the three
Phillips head screws on the rear cell of the tube. Turn each
collimation knob, one at a time, until the reflected image of the
collimating cap's dot in the secondary mirror is centered in the
primary mirror center mark ring. Once the telescope is col-
limated, tighten the Phillips head screws until you feel a slight
resistance. Do not over tighten the screws.
20
Support
screws
Collimation
screws
Figure 12.
Collimation adjustment screws for the StarSeeker
114mm and 130mm.
Figure 13.
To access the collimation adjustment screws, the rear
cover plate must first be removed.
Collimating the StarSeeker 130mm
To perform collimation adjustments, the rear cover plate must
first be removed. This is done by unthreading the three small
Phillips-head screws on the back of the mirror cell (Figure 13).
Once the cover plate is removed, the collimation adjustment
screws are accessible (Figure 12).
Collimation adjustments are made by adjusting the three pairs
of collimation screws. The collimation screws can be turned
with a Phillips head screwdriver and a 2.5mm hex key. Each
pair of collimation screws work together to adjust the align-
ment of the primary mirror; one screw must be loosened and
the other tightened by the same amount. Try tightening and
loosening one of the pairs of collimation screws by one turn.
Look into the focuser to see if the secondary mirror reflection
has moved closer to the center of the primary mirror reflec-
tion. The collimating cap makes this easy to see; watch if the
"dot" of the collimating cap is moving closer or farther away
from the ring on the center of the primary mirror. Repeat this
process on the other two pairs of collimation screws, if nec-
essary. It will take a little trial and error to get a feel for how
to adjust the screw pairs to center the dot of the collimating
cap in the ring of the primary mirror mark. Once the dot is
centered in the ring, the telescope is collimated, and the rear
cover plate can be reinstalled on the back of the mirror cell.
Rear
cover
plate