Viewfinder assembly Schmidt-Newtonian models

Cradle Assembly

Slot

Secondary

Lock Knob

Cradle Lock Knob

Fig. 7: Attach cradle to base mount- ing slot and tighten locking knobs.

Cradle Rings

Lock

Knobs

Fig. 8: Place optical tube in rings and loosely tighten cradle ring lock knobs.

Note: Model SC-8 users:

After completing step 6, refer to APPENDIX E, page 59, step 1, for information on how to attach the SC optical tube to the mount.

Viewfinder

Mounting

Screws and

Nuts

Fig. 9a: Viewfinder assembly,

Schmidt-Newtonian models.

Fig. 9b: Viewfinder assembly, refrac- tor models. Slide bracket into slot.

Unscrew the safety cap (23, Fig. 1d) from the shaft. Holding the counterweight (21, Fig. 1d) firmly in one hand, slip the counterweight to approximately the mid- point of the counterweight shaft (22, Fig. 1d). Tighten the counterweight lock knob to a firm feel. Replace the safety cap.

Note: If the counterweight ever slips, the safety cap (23, Fig. 1d) prevents the counterweight from sliding entirely off the shaft. Always leave the safety cap in place when the counterweight is on the shaft.

6.Set the latitude: Setting the latitude is easier if it is set before you attach the opti- cal tube to the assembly. Locate the latitude dial (28, Fig. 1d); note that there is a triangular pointer above the dial located on the mount. The pointer is not fixed; it moves as the mount moves.

Determine the latitude of your observing location. See APPENDIX C: LATITUDE CHART, page 54, for a list of latitudes, or check an atlas. Move the latitude T-han- dle screws in order to move the mount until the pointer points to your latitude. The two T-handle screws work in a "push - pull" operation—as you tighten one, loosen the other. When the pointer points at your latitude, tighten both screws until they make contact with the mount.

Also note that below the latitude T-handle screw located directly under the com- puter control panel is a star on top of the tripod leg. At your observing site, set up the telescope assembly so that this leg approximately faces North (or South in the Southern Hemisphere). Model SC-8 users, see APPENDIX E, page 59.

7.Attach the cradle assembly to the mount: Remove the optical tube from the cradle and slide the cradle assembly (11, Fig. 1a) onto the cradle mounting slot. See Fig. 7. The rounded base of the cradle assembly fits into the rounded por- tion of the mounting slot. Tighten both the cradle locking knob and the secondary locking knob to a firm feel.

8.Position optical tube: Unscrew the cradle ring lock knobs (13, Fig. 1a) and open the cradle rings. While firmly holding the optical tube (10, Fig. 1a), position it onto the cradle rings (14, Fig. 1a) with the mid-point of the optical tube’s length lying roughly in the center of the cradle ring assembly. Point the tube so that the front end (this end comes shipped with the dust cover (9, Fig. 1a) over it) is oriented as depicted in Fig. 1a. Then close the cradle rings (14, Fig. 1a) over the optical tube. Loosely tighten the cradle ring lock knobs just to hold the tube securely in place until you balance it. See BALANCING THE TELESCOPE, page 13.

9.Attach viewfinder bracket: Schmidt-Newtonian models (Fig. 9a): Locate the viewfinder bracket screws (15, Fig. 1b and Fig. 9a) and remove the nuts from the screws. Slide the holes in the viewfinder bracket over the viewfinder bracket screws. Replace the nuts and tighten to a firm feel only.

Attach viewfinder tube: Back off the viewfinder collimation screws (5, Fig. 1b) and slide the viewfinder tube into the bracket. Orient the viewfinder eyepiece as depicted in Fig. 1b. Tighten the collimation screws to a firm feel. See ALIGNING THE VIEWFINDER, page 14.

Attach viewfinder bracket: Achromatic refractor and Schmidt-Cassegrain

models (Fig. 9b): Slide the track on the bottom of the viewfinder bracket into the slot in the viewfinder mounting assembly (which is already attached to the tube). To secure the viewfinder to the mounting assembly, tighten the two thumbscrews to a firm feel only.

Attach viewfinder tube: Back off the viewfinder collimation screws (5, Fig. 1b) and slide the viewfinder tube into the bracket. Point the viewfinder eyepiece toward the focuser assembly. See Fig. 10b. Tighten the collimation screws to a firm feel. See ALIGNING THE VIEWFINDER, page 14.

10.Insert the eyepiece: Schmidt-Newtonian models (Fig. 10a): Lift to remove the dust cap from the eyepiece holder on the focuser assembly. Set the dust cap aside in a safe place and replace it when you have finished observing to protect the eyepiece assembly. Back off the eyepiece thumbscrews (1, Fig. 1a) and insert the supplied SP 26mm eyepiece (3, Fig. 1a) into the the eyepiece holder. Tighten the holder thumbscrews to a firm feel to secure the eyepiece.