User manual CELESTRON G-5 Instruction Manual

[. . . ] G-3 and G-5 Telescope Models #11090 / #11091 / #11050/ #11051 CG-3 Equatorial Mount Model #91503-A INSTRUCTION MANUAL Focuser Ring Finderscope Finder Bracket Eyepiece Star Diagonal ¼"x20 Photo Adapter Mounting Platform Mounting Block Photo Adapter Tightening Knob Fig 1 ­ G-3 Optical tube Corrector Plate Optical Tube Finderscope Finder Bracket Mounting Block (G-5 Only) ¼" x 20 Photo Adapter Mounting Platform (Used for the G-3) Declination Setting Circle R. A. Slow Motion Knob Counterweight Counterweight Locking Screw Eyepiece Star Diagonal Declination Locking Knob Declination Slow Motion Knob Right Ascension Setting Circle Latitude Adjustment Knob R. A. Spur Gear Figure 2 ­ The G-5 Telescope Azimuth Adjustment Knob Counterweight Shaft Counterweight Shaft Safety Screw Tripod Leg 2 INTRODUCTION Congratulations on your purchase and welcome to the Celestron world of astronomy. If you're a newcomer to the hobby of astronomy, some of the terms and telescope components described in this instruction manual may be new to you. [. . . ] Even if you are not using a motor drive, polar alignment is still desirable since it will reduce the number of corrections needed to follow an object and limit all corrections to one axis (R. A. ). There are several methods of polar alignment, all of which work on a similar principle, but are performed somewhat differently. For each hemisphere, there is a point in the sky around which all the other stars appear to rotate. These points are called the celestial poles and are named for the hemisphere in which they reside. For example, in the northern hemisphere all stars appear to move around the north celestial pole (see figure 8). When the telescope's polar axis is pointed at the celestial pole, it is parallel to the Earth's rotational axis. 10 Many of the methods of polar alignment require that you know how to find the celestial pole by identifying stars in the area. For those in the northern hemisphere, finding the celestial pole is not difficult. This star, Polaris, is the end star in the handle of the Little Dipper. Since the Little Dipper (technically called Ursa Minor) is not one of the brightest constellations in the sky, it may be difficult to locate, especially from urban areas. If this is the case, use the two end stars in the bowl of the Big Dipper. The position of the Big Dipper will change during the year and throughout the course of the night. When the Big Dipper is low in the sky (i. e. , near the horizon) it may be difficult to locate. Figure 8 Figure 9 To make finding and tracking the stars easier, a rough polar alignment is required. The right ascension (polar) axis should be pointed towards the North Pole (see figure 9). Set the latitude of the telescope to the latitude of your observing location by turning the azimuth adjustment screws on the mount. The latitude of your observing location corresponds to the altitude that Polaris will appear to be above the horizon. For example, If you are observing from Los Angeles, which has a latitude of 34°, then the celestial pole (and Polaris) will be 34° above the 11 northern horizon. All a latitude scale does then is to point the polar axis of the telescope at the right elevation above the northern (or southern) horizon. Release the DEC lock knob and move the telescope so that the tube is parallel to the polar axis. If the declination setting circle is not aligned, move the telescope so that the tube is parallel to the polar axis. In the case of the G-3 telescope, loosen the knob under the mounting plate (see figure 1) and slowly move the tube sideto-side on the mounting plate until Polaris is seen in the finderscope. Using the altitude and azimuth adjustment screws, move the mount until Polaris is in the field of view of the finderscope. You want to adjust the direction the polar axis is pointing and you are using the telescope to see where the polar axis is pointing. 5. 6. You are now polar aligned well enough to use your setting circles to find faint deep-sky objects. [. . . ] CI will repair or replace such product or part thereof which, upon inspection by CI, is found to be defective in materials or workmanship. As a condition to the obligation of CI to repair or replace such product, the product must be returned to CI together with proof-of-purchase satisfactory to CI. The Proper Return Authorization Number must be obtained from CI in advance of return. Call Celestron at (310) 328-9560 to receive the number to be displayed on the outside of your shipping container. [. . . ]