Celestron Advanced Series C6-R - Manual (Page 12)

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Eyepieces are commonly referred to by focal length and barrel diameter. The focal length of each eyepiece is
printed on the eyepiece barrel. The longer the focal length (i.e., the larger the number) the lower the eyepiece
magnification (i.e., power) and the shorter the focal length (i.e., the smaller the number) the higher the
magnification. Generally, you will use low-to-moderate power when viewing. For more information on how to
determine power, see the section on “Calculating Magnification.”
Your C6-R refracting telescope can use eyepieces with both a 1-1/4" barrel diameter and 2" barrel diameter. To use
a 2" barrel eyepiece, the 1 1/4" eyepiece adapter must first be removed. To do this, simply loosen the two chrome
thumbscrews located around the focuser barrel (see figure 2-11) and remove the 1 1/4" adapter. Once removed, a 2"
eyepiece or accessory can be inserted directly into the focuser barrel and secured with the two thumb screws.
B B a a l l a a n n c c i i n n g g t t h h e e T T u u b b e e i i n n R R . . A A . .
To eliminate undue stress on the mount, the telescope should be properly balanced around the polar axis. In
addition, proper balancing is crucial for accurate tracking if using an optional motor drive. To balance the mount:
1. Release the R.A. Clamp (see figure 2-15) and position the telescope off to one side of the mount (make sure that the
mounting bracket screw is tight). The counterweight bar will extend horizontally on the opposite side of the mount
(see figure 2-12).
2. Release the telescope — GRADUALLY — to see which way the telescope “rolls.”
3. Loosen the set screw on the counterweight.
4. Move the counterweight to a point where it balances the telescope (i.e., it remains stationary when the R.A. clamp is
released).
5. Tighten the set screw to hold the counterweight(s) in place.
These are general balance instructions and will reduce undue stress on the mount. When taking astrophotographs,
this balance process should be done for the specific area at which the telescope is pointing.
Balancing the Telescope in DEC
The telescope should also be balanced on the declination axis to prevent any sudden motions when the DEC clamp
(Fig 2-5) is released. To balance the telescope in DEC:
1. Release the R.A. clamp and rotate the telescope so that it is on one side of the mount (i.e., as described in the
previous section on balancing the telescope in R.A.).
2. Lock the R.A. clamp to hold the telescope in place.
3. Release the DEC clamp and rotate the telescope until the tube is parallel to the ground (see figure 2-13).
4. Release the tube — GRADUALLY — to see which way it rotates around the declination axis. DO NOT LET GO
OF THE TELESCOPE TUBE COMPLETELY!
5. Loosen the screws that hold the telescope tube inside the mounting rings and slide the telescope either forwards or
backwards until it remains stationary when the DEC clamp is released.
6. Tighten the tube ring screws firmly to hold the telescope in place.