Meade 4504 Lesson 4 Observing by Moving the Telescope Manually, Correctly positioned lever

IMPORTANT

NOTE:

Whenever you move your tele- scope, either man- ually or with Starfinder, position the levers of the R.A. and Dec locks so that they point upwards (see Fig. 10). An incorrectly positioned lever may strike and damage another piece of the tele- scope assembly while the telescope is moving.

Point

lever

upwards

Fig. 10: Correctly positioned lever.

NEVER point the telescope directly at or near the Sun at any time! Observing the Sun, even for the smallest fraction of a second, will result in instant and irreversible eye damage, as well as physical damage to the telescope itself.

5.Check this alignment on a celestial object, such as a bright star or the Moon, and make any necessary refinements, using the method outlined above in steps 3 and 4.

With this alignment performed, objects first located in the wide-field viewfinder will also be centered in the main telescope’s field of view. You are now ready to make your first observations with your telescope.

NOTE: The viewfinder and telescope present an upside-down image.

LESSON 4: Observing by Moving the Telescope Manually

This method describes how to make observations by manually moving the telescope.

After the telescope is assembled and balanced as described previously, you are ready to begin manual observations. View easy-to-find terrestrial objects such as street signs or traffic lights to become accustomed to the functions and operations of the tele- scope. For the best results during observations, follow the suggestions below:

•When you wish to locate an object to observe, first loosen the telescope’s R.A. lock (26, Fig. 2b) and Dec lock (27, Fig. 2b). The telescope can now turn freely on its axes. Also unlock the Azimuth lock (24, Fig. 2b). Unlock each axis separately and practice moving your telescope. Then practice with two or more unlocked axes at the same time. It is very important to practice this step to understand how your telescope moves, as the movement of an equatorial mount is not intuitive.

•Use the aligned viewfinder to sight-in on the object you wish to observe. When the object is centered in the viewfinder’s crosshairs, re-tighten the R.A. and Dec locks.

•A telescope’s eyepiece magnifies the image formed by the telescope’s main optics. Each eyepiece has a focal length, expressed in millimeters, or “mm.” The smaller the focal length, the higher the magnification. For example, an eyepiece with a focal length of 4mm has a higher magnification than an eyepiece with a focal length of 25mm. See "APPENDIX A," page 38 for more information.

Low-power magnification eyepieces offer a wide field of view, bright, high-contrast images, and relief of eye strain during long observing sessions. To observe an object with a telescope, always start with a low power eyepiece such as the H 25mm supplied with the 4504. When the object is centered and focused in the eyepiece, switch to a higher power eyepiece to enlarge the image as much as practical for prevailing viewing conditions.

NOTE: Viewing conditions vary widely from night-to-night and site-to-site. Turbulence in the air, even on an apparently clear night, can distort images. If an image appears fuzzy and ill-defined, back off to a low-power eyepiece for a more well-resolved image.

•The Barlow lens included with your telescope triples the eyepiece magnification. See "APPENDIX A," page 38 for more information.

•Once centered, an object can be focused by turning one of the knobs of the focusing mechanism (17, Fig. 2b). Notice that when observing astronomical objects, the field of view begins to slowly drift across the eyepiece field. This motion is caused by the rotation of the Earth on its axis. Objects appear to move through the field more rapidly at higher powers. See "APPENDIX B," page 39, for detailed information. Lesson 6 will explain how you can counteract the drift in the field of view.

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