Using the Setting Circles
Once the setting circles are aligned you can use them to find any object with known coordinates.
1. Select an object to observe. Use a seasonal star chart or planisphere to make sure the object you chose is above the horizon. As you become more familiar with the night sky, this will no longer be necessary.
2. Look up the coordinates in an atlas or reference book.
3. Move the telescope in declination until the indicator is pointing at the correct declination coordinate.
4. Move the telescope in R.A. until the indicator points to the correct coordi- nate (do NOT move the R.A. circle). The telescope will track in R.A. as long as a motor drive is operating and the R.A. clamp is in the locked position.
5. Look through the finder to see if you have located the object.
6. Center the object in the finder.
7. Look in the main optics using a low power eyepiece; the object should be there. The telescope will track in R.A. as long as the motor drive is operating.
8. Repeat the process for each object observed throughout the observing session.
You may not be able to see fainter objects in the finder. When this happens, gradually sweep the telescope around until the object is visible.
The declination setting circle is scaled in degrees while the R.A. setting circle is incremented in minutes with a marker every fifth minute. As a result, the setting circles will get you close to your target, but not directly on it. Also, the accuracy of your polar alignment will also affect how accurately your setting circles read.
At the end of this manual there is a list of
42 • Celestial Observing