Telescope Maintenance - Celestron G-3 Instruction Manual

Once the setting circles are aligned you can use them to find any objects with known coordinates. The
accuracy of your setting circles is directly related to the accuracy of your polar alignment.
1. Select an object to observe. Use a seasonal star chart 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. Hold the telescope and release the DEC locking knob.
4. Move the telescope in declination until the indicator is pointing at the correct declination coordinate.
5. Tighten the declination lock knob to prevent the telescope from moving.
6. Hold the telescope and release the R.A. lock knob.
7. Move the telescope in R.A. until the indicator points to the correct coordinate.
8. Tighten the R.A. lock knob to prevent the telescope from slipping in R.A. The telescope will track in
R.A. as long as the clock drive is operating.
9. Look through the finderscope to see if you have located the object.
10. Center the object in the finder.
11. Look in the main optics and the object should be there. For some of the fainter objects, you may not be
able to see them in the finder. When this happens, it is a good idea to have a star chart of the area so
that you can "star hop" through the field to your target.
This process can be repeated for each object throughout any given night.
With proper care your telescope should rarely need any maintenance work.
When not in use, always replace all lens covers to keep dust and contaminants off the optical surfaces.
A small amount of dust on any optical surface is OK. If the dust builds up then use a can of
compressed air and then a camel's hair brush to remove the dust.
If the mirrors or lenses need cleaning, they should be cleaned by a professional. Either have your
instrument serviced by a telescope repair facility or return it to the factory.
Collimation or alignment of the optical system is done at the factory before shipment.
Collimation (for the G-5 telescope only)
The optical performance of your Celestron telescope is directly related to its collimation, the alignment of
its optical system. Your Celestron G-5 was collimated at the factory after it was completely assembled.
However due to the optical design of the G-5 telescope, the tilt of the secondary mirror may need to be
adjusted by the user. The optical design of the G-3 telescope does not have a moveable secondary mirror,
therefore no adjustments in collimation needs to be made. If however the telescope is dropped or jarred
severely, it may have to be collimated. Should the G-3 optical tube become out of alignment, it should be
returned to the factory for professional collimation. However, if your G-5 should come out of collimation,
you can perform the following procedures to re-collimate the optical system.

Telescope Maintenance

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