Date circle

Ring with engraved time meridian indicator mark

Polar scope alignment thumbscrew (3)

R.A. setting circle lock thumbscrew

Pointer

R.A. setting circle

Meridian offset scale

Polar scope housing

Polar axis finder scope

Figure 2. To adjust the latitude angle of the equatorial mount, loosen one of the two latitude adjustment T-bolts, then tighten the other.

7.Remove the knurled “toe saver” retaining screw on the bot- tom 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 on 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 two slow-motion cables to the R.A. and Dec. worm gear shafts of the equatorial mount by positioning the small screw on the end of the cable over the indented slot on either end of the worm gear shaft. Then tighten the screw. We recommend using the shorter control cable for the R.A. axis.

9.Install the polar axis finder scope into its housing inside the R.A. axis of the equatorial mount (Figure 3). First loosen the three thumbscrews on the housing, which is located at the rear of the R.A. axis. Insert the front end of the polar finder (the end without the eyeguard) into the housing so only about 1" of the polar finder extends from the back of the housing. Do this slowly and with a twisting motion to prevent the internal O-ring from becoming unseated. Should the O-ring become unseated, remove the entire housing from the mount to locate the O-ring and reseat it by rotating the entire housing counterclockwise. Once the polar axis finder scope is in the housing, tighten the three thumbscrews. These thumbscrews will be used later to align the finder with the mount’s R.A. axis.

4. Attaching a Telescope

The AstroView equatorial mount is designed to hold telescope tubes weighing up to approximately 12lbs. For heavier tele- scopes, the mount may not provide sufficient stability for steady imaging. Any type of telescope can be mounted on the AstroView, including refractors, Newtonian reflectors, and cat-

Figure 3. The polar axis finder scope installed in the right ascension (R.A.) axis of the mount.

adiotropics, provided a set of tube rings is available to couple the tube to the mount. Orion sells a variety of telescope tube rings, please visit our website at telescope.com for details. To attach the tube rings to the mount, you will need to line up the holes in the tube rings with the holes in the top of the mount. Push a mounting screw up through the hole in the top of the mount and thread it into the tube ring. Use a wrench to tighten the screw and secure the tube ring.

5. Balancing a Telescope

To ensure smooth movement of a 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 R.A. axis, then the Dec. 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 R.A. axis. Rotate it until the counterweight 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 4a) That’s the point at which the shaft remains horizontal even when you let go with both hands (Figure 4b).

3.Retighten the counterweight lock knobs. The telescope is now balanced on the R.A. axis.

4.To balance the telescope on the Dec. axis, first tighten the R.A. lock lever, with the counterweight shaft still in the hor- izontal position.

5.With one hand on the telescope optical tube, loosen the Dec. lock lever. The telescope should now be able to rotate freely about the Dec. axis. Loosen the tube ring clamps a few turns, until you can slide the telescope tube forward and back inside the rings. Its often helpful to use a slight twisting motion on the optical tube while you push or pull on it. (Figure 4c).

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Orion 9822 instruction manual Attaching a Telescope, Balancing a Telescope