Orion 9829 instruction manual Attaching a Telescope, Balancing a Telescope

er on the center support shaft against the tray, and follow it by threading the securing knob all the way up the center support shaft until it is tight against the tray. The tripod support tray provides additional stability for the tripod, and holds up to five 1.25" eyepieces and two 2" eyepieces.

6.Thread the counterweight shaft into the equatorial mount at the base of the declination axis until tight. Make sure the casting at the top is threaded clockwise as far as it will go before attaching the shaft. Then turn the casting counter- clockwise one the shaft is installed until the top of the cast- ing is flush with the mount.

7.Remove the knurled “toe saver” retaining screw on the bottom of the counterweight shaft and slide both counter- weights onto the shaft. Make sure the counterweight lock knobs are adequately loosened to allow the counterweight shaft to pass through the hole. Position the counterweights about halfway up the shaft and tighten the lock knobs. Replace the toe saver at the end of the bar. The toe saver prevents the counterweights from falling on your foot if the lock knobs happen to come loose.

8.Attach the slow-motion control knobs to the right ascen- sion and declination gear shafts of the equatorial mount by sliding them onto the shafts. Line up the flat end of the gear shaft with the interior of the knob. The knobs can be attached to either end of the shafts, whichever is more convenient for you.

Your SkyView Pro EQ mount is now fully assembled and should resemble Figure 1.

4. Attaching a Telescope

The SkyView Pro equatorial mount is designed to hold tele- scope tubes weighing up to approximately 20 lbs. For heavier telescopes, the mount may not provide sufficient stability for steady imaging. Any type of telescope can be mounted on the SkyView Pro, including refractors, Newtonian reflectors, and catadiotropics, provided a set of tube rings is available to cou- ple the tube to the mount. Orion sells a variety of telescope tube rings. Please visit our website at telescope.com for details.

1.Attach the tube mounting rings to the tube mounting plate using the attachment screws that came with tube rings. The screws should go through the holes on the outer ends of the mounting plate and rethread into the tube rings. Note that the side of the mounting plate with the central “groove” will be facing up.

2.Loosen the black mounting plate securing knob as well as the metal safety screw on the top of the equatorial mount. Place the mounting plate, with the tube rings attached, in the dovetail slot on top of the equatorial mount. Position the mounting plate so that it is centered on the dovetail slot. Re-tighten the mounting plate securing knob until the mounting plate is secure. Then, tighten the safety screw. The safety screw will ensure that the mounting plate (and telescope tube) will not fall off the EQ mount if the mount- ing plate securing knob should come loose.

a.b.

c.d.

Figure 3. Proper operation of the equatorial mount requires that the telescope tube be balanced on both the R.A. and Dec. axes. (a) With the R.A. lock lever released, slide the counterweights along the counterweight shaft until it just counterbalances the tube. (b) When you let go with both hands, the tube should not drift up or down. (c) With the Dec. lock knob released, loosen the tube ring lock clamps a few turns ands slide the telescope forward or back in the tube rings. (d) When the tube is balanced about the Dec. axis, it will not move when you let go.

3.Open the tube rings and lay the telescope optical tube in the rings at about the midpoint of the tube’s length. Rotate the tube so that the focuser is at a convenient height for viewing. Close the tube rings and tighten them.

5. Balancing a Telescope

To ensure smooth movement of the telescope on both axes of the equatorial mount, it is imperative that the optical tube is properly balanced. We will first balance the telescope with respect to the right ascension axis, then the declination axis.

1.Keeping one hand on the telescope optical tube, loosen the R.A. lock lever. Make sure the Dec. lock lever is locked, for now. The telescope should now be able to rotate freely about the right ascension axis. Rotate it until the counter- weight shaft is parallel to the ground (i.e., horizontal).

2.Now loosen both counterweight lock knobs and slide the weights along the shaft until they exactly counterbalance the telescope (Figure 3a). That’s the point at which the shaft remains horizontal even when you let go with both hands (Figure 3b). If the telescope refuses to balance, then you have either too much or too little counterweight. Remove a counterweight if it is too much, or add optional counterweights if it is too little.

3.Retighten the counterweight lock knobs. The telescope is now balanced on the right ascension axis.

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