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Battery Compartment
To align the Star Pointer finderscope:
1.
To turn on the Star Pointer, turn the switch to the "on" position – see Figure 3-4.
2.
Locate a bright star or planet and center it in a low power eyepiece in the main telescope.
3.
With both eyes open, look through the glass window at the alignment star.
If the Star Pointer is perfectly aligned, you will see the red LED dot overlap the alignment star. If the Star
Pointer is not aligned, take notice of where the red dot is relative to the bright star.
4.
Without moving the main telescope, turn the Star Pointer's two adjustment screws until the red dot is directly
over the alignment star. Experiment as to which way each screw moves the red dot.
5.
The Star Pointer is now ready for use. Always turn the power off after you have found an object. This will
extend the life of both the battery and the LED.
Note:
Your battery may be installed already. If not, open the battery compartment – see Figure 3-4 with a thin
coin or screwdriver. Put the battery in with the "+" sign facing out. Then put the battery compartment back
on. If you ever need to replace the battery, it is a 3-volt lithium type # CR 1620.
Comment: The LED brightness does not have a brightness adjustment. It was designed to work in all locations
where it can have enough brightness for urban areas and yet not be too bright for use in rural areas.
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You can change the power of your
magnification of your telescope, simply divide the focal length of the telescope by the focal length of the eyepiece
used. In equation format, the formula looks like this:
Magnification =
Let's say, for example, you are using the 20mm eyepiece that came with your telescope. To determine the
magnification you simply divide the focal length of your telescope (the AstroMaster 70 EQ for this example has a
focal length of 900mm) by the focal length of the eyepiece, 20mm. Dividing 900 by 20 yields a magnification of 45
power.
Although the power is variable, each instrument under average skies has a limit to the highest useful magnification.
The general rule is that 60 power can be used for every inch of aperture. For example, the AstroMaster 70 EQ is
2.8" inches in diameter. Multiplying 2.8 by 60 gives a maximum useful magnification of 168 power. Although this
is the maximum useful magnification, most observing is done in the range of 20 to 35 power for every inch of
aperture which is 56 to 98 times for the AstroMaster 70 EQ telescope. You can determine the magnification for
your telescope the same way.
Figure 3-4
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telescope just by changing the eyepiece (ocular).
Focal Length of Telescope (mm)
Focal Length of Eyepiece (mm)
On/Off
Switch
14
Figure 3-5
To determine the
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