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Toward the front of the telescope tube, near the focusing assembly, there is a small bracket with a set screw in it. This is where the finderscope bracket will be mounted. To install the finderscope: 1. Slide the rubber O-ring over the eyepiece end of the finderscope and roll it 2/3 of the way up the finderscope. 2. Insert the eyepiece end of the finderscope through the bracket until the O-ring presses tightly between the finder and the inside of the bracket. 3. Tighten the three adjustment screws until they make contact with the finderscope body. 4. Locate the mounting bracket near the front (open) end of the telescope. 5. Loosen the set screw on the mounting bracket on the telescope. 6. Slide the finder bracket (attached to the finderscope) into the mounting bracket on the telescope. 7. The finderscope bracket will slide in from the back. The finderscope should be oriented so that the objective lens is toward the front (open) end of the telescope (see figure 3). 8. Tighten the set screw on the mounting bracket to hold the finderscope in place. Figure 3 Attaching the Finderscope (for #31027) 1. Remove the nuts from the studs where the finderscope will mount (see figure 4). 2. Mount the finderscope bracket (#4) by mounting the bracket over the studs protruding from the tube and tightening it down with the supplied nuts. 3. Slide the rubber O-ring over the eyepiece end of the finderscope and roll it 2/3 of the way up the finderscope. 4. Insert the eyepiece end of the finderscope through the bracket until the O-ring presses tightly between the finder and the inside of the bracket. 5. Tighten the three adjustment screws until they make contact with the finderscope body. The finderscope is now installed and only needs to be aligned before it is used. Figure 4 Attaching the Accessories In order to use your telescope there are some standard accessories which must first be installed: The installation of each is described 1 ." Diagonal (for #21077 & #21016): Loosen the thumb screw on the eyepiece holder located on the focuser draw tube. Slide the smaller end of the diagonal (without the thumb screw) into the focuser tube. Tighten the thumb screw to hold the diagonal in place. Ocular: Loosen the thumb screw on the eyepiece holder (or 1 ." diagonal for #21077 & #21016). Slide the barrel of the eyepiece into the eyepiece holder and tighten the thumb screw to hold the eyepiece in place. Aligning the Finderscope Accurate alignment of the finderscope makes it easy to find objects with the telescope, especially celestial objects. To make aligning the finderscope as easy as possible, this procedure should be done in the daytime when it is easy to find and identify objects. To align the finder: 1. Choose a target that is in excess of one mile away. This will eliminate any possible parallax effect between the telescope and finderscope. 2. Point the telescope at your target and center it in the main optics of the telescope. You may have to move the telescope slightly to center your target. 3. Adjust the screws on the finderscope bracket, tightening one while loosening another, until the cross hairs are centered on the target seen through the telescope. 4. Tighten the lock nuts to secure the position of the finderscope. Image orientation through the finder will be inverted (i.e., upside down and backwards left-to-right). This is normal for any finderscope that is used straight-through. Because of this, it may take a few minutes to familiarize yourself with the directional change each screw makes on the finderscope. Telescope Basics Calculating Magnification The magnification (or power) of a telescope is variable depending upon the focal length of the eyepiece being used along with the focal length of the telescope. To calculate the magnification we use the following formula: FL telescope ) ( Magnification = FL eyepiece ) ( where FL(telescope) is the focal length of the telescope and FL(eyepiece) is the focal length of the eyepiece. For example, if the focal length of the telescope is 910mm and you use a 20mm eyepiece your magnification is 910/20 = 46x. There are numerous optional eyepieces that are available to expand your range of magnification. There are various types of eyepieces of varying quality to choose from. The Celestial - Coordinate System. The celestial-coordinate system is an imaginary projection of the Earth's geographical coordinate system onto the celestial sphere which seems to turn overhead at night. This celestial grid is complete with equator, latitudes, longitudes and poles. The Earth is in constant motion as it rotates on its axis. Actually the celestial-coordinate system is being displaced very slowly with respect to the stars. This is called precession and is caused by gravitational influences from the Sun, Moon and other celestial bodies. The celestial equator is a full 360. circle bisecting the celestial sphere into the northern celestial hemisphere and the southern celestial hemisphere. Like the Eart...

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