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This document provides some guidelines and tips for C-14 observations using a standard Mark I eyeball as the detector.

LOCAL CONDITIONS AND TARGET SELECTION
1. Unless you are planning to look at a bright object (mV < 2), you will probably have to wait until an hour or more after sunset for the sky to become sufficiently dark.

2. Even well after sundown, the sky brightness is quite high, due to light pollution from nearby streetlights and security lights, and the surrounding megopolis. Point sources dimmer than 10th magnitude are probably invisible, and extended objects will have an even lower (brighter) magnitude limit.

3. Near the horizon to the south, the heating plant is pumping hot air into the sky, so the seeing is really bad. A security lamp to the north will shine directly on the scope aperture for azimuth = +/- 30 deg, but this can be screened by wedging the large styrofoam sheet in the lower part of the dome slit. The best direction to see dim objects is, of course, at the zenith, but east and west azimuths are not too bad. Plan your target selection accordingly.

4. If you're looking for ideas for things to observe, Burnham's Celestial Atlas, which should be on the desk or the bookshelf, lists many multiple stars, nebulae, and other astronomical showpieces, and Sky & Telescope Magazine is also a good resource for targets. In addition, RDRO will gradually compile a list of good targets

SETUP
1. Follow the instructions in Dome and Telescope Setup to properly open the dome and align the telescope.

2. Wait for night to fall fully before trying for any dim objects. Also, give your eyes at least 15 minutes to fully dark-adjust after you turn off all white lights in the dome.

EYEPIECE SELECTION
1. The eyepiece case contains an assortment of different eyepieces, currently 40 mm, 25 mm, and 15 mm. Choose an eyepiece appropriate to the object you want to look at. Longer focal lengths (40 mm) will give you a wider field of view; shorter focal lengths (15 mm) will result in a smaller FOV at a higher magnification. With the poor seeing, the 15 mm eyepiece will probably just give you an enlarged view of a fuzzy object. 2. There is also a 2.5x Barlow lens, which when used with a given eyepiece, will produce an even more highly magnified field, at the cost of throughput.

3. There is a "Nebular Filter" in the eyepiece box, which is intended to enhance the green wavelengths emitted by planetary nebulae and some planets. Remove the eyepiece and screw the filter into the base of the eyepiece. Reinsert the eyepiece.

POINTING
1. When moving the telescope over large angles, grab the grey Y-yoke or the rails on top and bottom of the main scope tube, and push or pull. Do not use the eyepiece diagonal or the finderscope as a handle.

2. If you can locate your target object with the naked eye, align the scope the the object by sighting along the rails on the main tube.

3. If you have RA and dec coordinates for the object (and if you calibrated the setting circles as described in the Setup document), then you can simply move the scope to those coordinates. Beware of confusing north (+) and south (-) declinations.

4. The target should now be in the finderscope. Move it to the crosshair center with gentle tugs on the yoke and main scope tube. The pushbutton paddle controls can be used for the fine alignment.

5. The target should now be visible in the main scope eyepiece. Center it with the paddle controls, and make any fine focus adjustments necessary.

6. Marvel at the splendors of the universe.


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