User manual ORION TELESCOPES & BINOCULARS 09802

[. . . ] INSTRUCTION MANUAL Orion Observer 70mm EQ ® TM #9802 Equatorial Refracting Telescope 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 096 Rev. A 0898 Tube rings Tube ring clamps Objective lens Dew shield Tube ring mounting bolt Declination setting circle Right ascension lock knob (hidden) Counterweight shaft Counterweight Counterweight lock knob Retaining washer and screw Azimuth lock knob (hidden) Tripod leg attachment bolt Accessary tray bracket Accessory tray Tripod leg Finder scope Finder scope bracket Finder scope alignment screws (3) Focuser drawtube Eyepiece Star diagonal Focus knob Declination slow-motion control Declination lock knob Latitude lock knob (hidden) Latitude scale Right ascension setting circle Right ascension slow-motion control Leg lock thumbscrew Figure 1. Observer 70 EQ Parts Diagram 2 Congratulations on your purchase of a quality Orion telescope. [. . . ] Most setting circles are not accurate enough to put an object dead-center in your finder scope's field of view, but they'll get you close, assuming the equatorial mount is accurately polaraligned. setting circle must be recalibrated every time you wish to locate a new object. Do so by calibrating the setting circle for the centered object before moving on to the next one. 6. Using the Telescope-- Astronomical Observing Choosing an Observing Site When selecting a location for observing, get as far away as possible from direct artificial light such as street lights, porch lights, and automobile headlights. The glare from these lights will greatly impair your dark-adapted night vision. Set up on a grass or dirt surface, not asphalt, because asphalt radiates more heat, which disturbs the surrounding air and degrades the images seen through the telescope. Avoid viewing over rooftops and chimneys, as they often have warm air currents rising from them. Similarly, avoid observing from indoors through an open (or closed) window, because the temperature difference between the indoor and outdoor air will cause image blurring and distortion. If at all possible, escape the light-polluted city sky and head for darker country skies. You'll be amazed at how many more stars and deep-sky objects are visible in a dark sky!Cooling the Telescope All optical instruments need time to reach "thermal equilibrium. " The bigger the instrument and the larger the temperature change, the more time is needed. Allow at least a half-hour for your telescope to cool to the temperature outdoors. In very cold climates (below freezing), it is essential to store the telescope as cold as possible. If it has to adjust to more than a 40° temperature change, allow at least one hour. R. A. ­5° 27' That's 5 hours and 35. 4 minutes in right ascension, and ­5 degrees (5 degrees south of the celestial equator) and 27 minutes in declination. Before you can use the setting circles to locate objects, they must first be calibrated. The declination setting circle was calibrated at the factory, and should read 90° when the telescope optical tube is pointing exactly along the polar axis. If it does not read 90°, it may have to be reset. Calibrating the Right Ascension Setting Circle 1. Identify a bright star near the celestial equator and look up its coordinates in a star atlas. 6 Aiming the Telescope To view an object in the main telescope, first loosen both the R. A. Aim the telescope at the object you wish to observe by "eyeballing" along the length of the telescope tube (or use the setting circles to "dial in" the object's coordinates). Then look through the (aligned) finder scope and move the telescope tube until the object is centered on the crosshairs. [. . . ] If you wish, you may apply some auto touch-up paint to the scratch. Smudges on the tube can be wiped off with a soft cloth and a household cleaner such as Windex or Formula 409. Cleaning the Optics A small amount of dust or a few specks on the glass objective (main) lens will not affect the performance of the telescope. If dust builds up, however, simply blow it off with a blower bulb, or lightly brush it off with a soft camel-hair brush. [. . . ]