INSTRUCTION MANUAL Orion EQ-2 Equatorial Mount ® #9828 Equatorial Mount Customer Support (800) 676-1343 E-mail: support@telescope.com Corporate Offices (831) 763-7000 Providing Exceptional Consumer Optical Products Since 1975 P.O. Box 1815, Santa Cruz, CA 95061 IN 168 Rev. A 0719 Dec. setting circle R.A. setting circle Latitude lock t-bolt Latitude adjustment t-bolt Dec. slow-motion control cable Counterweight shaft Azimuth lock knob R.A. slow-motion control cable Counterweight Counterweight lock knob Accessory tray Accessory tray bracket Accessory tray bracket attachment point Leg lock knob Figure 1. EQ-2 Mount Congratulations on your purchase of a quality Orion product. Your new EQ-2 Equatorial Mount was designed to work with many different telescope optical tubes. Designed for astronomical use, this precision mount allows convenient manual "tracking" of celestial objects as they move slowly across the sky, so they remain within your eyepiece's field of view. The setting circles will assist you in locating hundreds of fascinating celestial denizens, including galaxies, nebulas, and star clusters, from their catalogued coordinates. With a little practice and a little patience, you'll find that your EQ-2 Equatorial Mount is an invaluable tool for getting the most out of your astronomical observing sessions. These instructions will help you set up and properly use your equatorial mount. Please read them over thoroughly before getting started. 2 Table of Contents 1. Unpacking ............................................................................................................................. 3 2. Assembly .............................................................................................................................. 3 3. Attaching a Telescope........................................................................................................... 4 4. Balancing a Telescope .......................................................................................................... 4 5. Setting Up and Using the Equatorial Mount............................................................................ 5 6. Specifications.......................................................................................................................... 8 1. Unpacking The entire mount will arrive in one box. Be careful unpacking the box. We recommend keeping the box and all the internal shipping containers. In the event that the mount needs to be shipped to another location, or returned to Orion for warranty repair, having the proper box and internal shipping containers will help ensure that your mount will survive the journey intact. Make sure all the parts in the Parts List are present. Be sure to check all packaging carefully, as some parts are small. If anything appears to be missing or broken, immediately call Orion Customer Support (800-676-1343) or email support@telescope.com for assistance. Parts List Box #1: Optical Tube Assembly and Accessories Qty. Description 1 2 1 1 3 1 1 German-type equatorial mount Slow-motion control cables Counterweight Counterweight shaft Tripod legs w/attachment bolts Tripod accessory tray w/mounting hardware Accessory tray bracket 2. Assembly Assembling the mount for the first time should take about 20 minutes. No tools are needed, other than the ones provided. All bolts should be tightened securely to eliminate flexing and wobbling, but be careful not to over-tighten or the threads may strip. Refer to Figure 1 during the assembly process. 1. Lay the equatorial mount on its side. Attach the tripod legs one at a time to the mount by sliding the bolts installed in the tops of the tripod legs into the slots at the base of the mount and tightening the wing nuts finger-tight. Note that the accessory tray bracket attachment point on each leg should face inward. 2. Tighten the leg lock knobs on the bottom braces of the tripod legs. For now, keep the legs at their shortest (fully retracted) length; you can extend them to a more desirable length later, after the telescope is completely assembled. 3. With the tripod legs now attached to the equatorial mount, stand the tripod upright (be careful!) and spread the legs apart enough to connect each end of the accessory tray bracket to the attachment point on each leg. Use the screw that comes installed in each attachment point to do this. First remove the screw using the supplied screwdriver, then line up one of the ends of the bracket with the attachment point and reinstall the screw. Make sure that the accessory tray bracket is oriented so that the ribs in its plastic molding face downwards. 4. Now, with the accessory tray bracket attached, spread the tripod legs apart as far as they will go, until the bracket is taut. 5. Attach the accessory tray to the accessory tray bracket with the three wing screws already installed in the tray. This is done by pushing the wing screws up through the holes in the accessory tray bracket, and threading them into the holes in the accessory tray. 6. Next, tighten the bolts at the tops of the tripod legs, so the legs are securely fastened to the equatorial mount. Use the provided wrench and your fingers to do this. 7. Orient the equatorial mount as it appears in Figure 2, at a latitude of about 40°, i.e., so the pointer next to the latitude scale (located directly above the latitude lock t-bolt) is pointing to the mark at "40." To do this, loosen the latitude lock t-bolt, and turn the latitude adjustment t-bolt until the pointer and the "40" line up. Then retighten the latitude lock t-bolt. The declination (Dec.) and right ascension (R.A.) axes may need re-positioning (rotation) as well. Be sure to loosen the R.A. and Dec. lock knobs before doing this. 3 Retighten the R.A. and Dec. lock knobs once the equatorial mount is properly oriented. 8. Slide the counterweight onto the counterweight shaft. Make sure the counterweight lock knob is adequately loosened to allow the counterweight shaft to pass through the hole in the counterweight. 9. Now, with the counterweight lock knob still loose, grip the counterweight with one hand and thread the shaft into the equatorial mount (at the base of the declination axis) with the other hand. When it is threaded as far in as it will go, position the counterweight about halfway up the shaft and tighten the counterweight lock knob. The retaining screw and washer on the bottom of the shaft prevent the counterweight from falling off (and onto your foot!) if the counterweight lock knob becomes loose. 10.Attach the two slow-motion cables to the R.A. and Dec. worm gear shafts of the equatorial mount by positioning the thumb screw on the end of the cable over the indented slot on the worm gear shaft and then tightening the thumb screw. We recommend that the shorter cable be used on the R.A. worm gear shaft and the longer cable on the Dec. worm gear shaft. The equatorial mount is now fully assembled and should appear as shown in Figure 1. Figure 2. The equatorial mount. 3. Attaching A Telescope The EQ-2 Equatorial Mount is designed to hold small to midsize telescopes weighing up to about 10 lbs. For heavier telescopes, the mount may not provide sufficient stability for steady imaging. Any type of telescope can be mounted on the EQ-2 Equatorial mount, including refractors, Newtonian reflectors, and cadadioptrics, provided a 1/4"-20 adapter or set of tube rings is available to couple the tube to the mount. Orion carries a variety of differently sized tube rings and a 1/4"-20 mounting adapter designed exclusively for the EQ-2 Equatorial Mount. One of these items probably fits the telescope tube you wish to mount. Check the Orion print or online catalogs for currently available mounting accessories. 4. Balancing the Telescope Once the telescope is attached to the equatorial mount, the next step is to balance the telescope. Proper balance is required to insure smooth movement of the telescope on both axes of the equatorial mount. If you attach your telescope with a 1/4"-20 adapter, it may not be possible to balance the scope precisely with respect to the Dec. lock knob R.A. lock knob Dec. slow-motion control cable Dec. setting circle N IO AT IN CL DE T GH RI N IO NS CE AS IS AX IS AX Latitude scale Latitude adjustment t-bolt Latitude lock t-bolt Azimuth lock knob R.A. setting circle lock thumbscrew R.A. setting circle R.A. slow- motion control cable 4 3a 3b 5. Loosen the tube ring clamps a few turns until you can slide the telescope tube forward and back inside the rings (this can be aided by using a slight twisting motion on the optical tube while you push or pull on it). Position the telescope so that it remains horizontal when you carefully let go with both hands. This is the balance point for the Dec. axis (Figure 3d). Before clamping the rings tight again, rotate the telescope so that the eyepiece is at a convenient angle for viewing. The telescope is now balanced on both axes. Now when you loosen the lock knob on one or both axes and manually point the telescope, it should move without resistance and should not drift from where you point it. 3c 3d 5. Setting Up and Using the Equatorial Mount Figure 3A, 3B, 3C, 3D: Proper operation of the equatorial mount requires balancing the telescope tube on the R.A. axis. (a) With the R.A. lock knob released, slide the counterweight 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 and 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. When you look at the night sky, you no doubt have noticed that the stars appear to move slowly from east to west over time. That apparent motion is caused by the Earth's rotation (from west to east). An equatorial mount (Figure 2) is designed to compensate for that motion, allowing you to easily "track" the movement of astronomical objects, thereby keeping them from drifting out of the telescope's field of view while you're observing. This is accomplished by slowly rotating the telescope on its right ascension (R.A.) axis, using only the R.A. slow-motion cable. But first the R.A. axis of the mount must be aligned with the Earth's rotational (polar) axis - a process called polar alignment. Polar Alignment For Northern Hemisphere observers, approximate polar alignment is achieved by pointing the mount's R.A. axis at the North Star, or Polaris. It lies within 1° of the north celestial pole (NCP), which is an extension of the Earth's rotational axis out into space. Stars in the Northern Hemisphere appear to revolve around the NCP. To find Polaris in the sky, look north and locate the pattern of the Big Dipper (Figure 4). The two stars at the end of the "bowl" of the Big Dipper point right to Polaris. Observers in the Southern Hemisphere aren't so fortunate to have a bright star so near the south celestial pole (SCP). The star Sigma Octantis lies about 1° from the SCP, but it is barely visible with the naked eye (magnitude 5.5). For general visual observation, an approximate polar alignment is sufficient. Level the equatorial mount by adjusting the length of the three tripod legs. Loosen the latitude lock t-bolt. Turn the latitude adjustment tbolt and tilt the mount until the pointer on the latitude scale is set at the latitude of your observing site. If you don't know your latitude, consult a geographical atlas to find it. For example, if your latitude is 35° North, set the pointer to 35. Then retighten the latitude lock t-bolt. The latitude setting should not have to be adjusted again unless you move to a different viewing location some distance away. 5 declination axis. This is because the telescope cannot be repositioned as it can when tube rings are used. Assuming you will be using tube rings, 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 knob. Make sure the Dec. lock knob 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 the counterweight lock knob and slide the weight along the shaft until it exactly counterbalances the telescope (Figure 3a). That's the point at which the shaft remains horizontal even when you let go of the telescope with both hands (Figure 3b). If you position the counterweight all the way at the end of the shaft (near the retaining bolt and washer) and it still does not counterbalance the telescope, you will need to purchase an additional counterweight. Retighten the counterweight lock knob. The telescope is now balanced on the R.A. axis. 3. To balance the telescope on th ...