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The method for precise polar alignment—commonly referred to
as the "drift" method—is as follows:
a.
Obtain a rough polar alignment as described above. Once
approximate alignment has been accomplished, insert the
2x Barlow lens and the illuminated reticle eyepiece into
the telescope's eyepiece holder.
b.
With the motor drive running, point the telescope at a
moderately bright star near where the meridian (the north-
south line passing through your local zenith) and the
celestial equator intersect. For best results, the star
should be located within +/-30 minutes in R.A. of the
meridian and within +/- 5° in Dec of the celestial equator.
Pointing the telescope at a star that is straight up, and
then moving the telescope in Dec to read 0° Dec, will point
the telescope to the correct position.
c.
Disregarding the drift in R.A., note the star's drift in
Declination:
1. If the star drifts South (or down), the telescope's
polar axis is pointing too far East (Fig. 16).
2. If the star drifts North (or up), the telescope's polar
axis is pointing too far West (Fig. 17).
d.
Move the wedge in azimuth (horizontal) to change the
polar alignment. Reposition the east-west polar axis
Polaris
Fig.16: Telescope too far East
orientation until there is no further north-south drift by the
star. Track the star for a period of time to be certain that
its Declination drift has ceased.
e.
Next, point the telescope at another moderately bright star
near the Eastern horizon, but still near the celestial
equator. For best results, the star should be about 20° or
30° above the Eastern horizon and within +/- 5° of the
celestial equator (i.e., still at about 0° Dec).
f.
Once again, note the star 's drift in Declination:
a. If the star drifts South (or down), the telescope's
polar axis is pointing too low (Fig. 18).
b. If the star drifts North (or up), the telescope's polar
axis is pointing too high (Fig. 19).
g.
Use the fine latitude adjustment on the equatorial wedge
(7, Fig. 4) to change the latitude angle based on your
observations above. Again, track the star for a period of
time to verify that Declination drift has ceased.
After completing these procedures your telescope is precisely
polar aligned, minimizing the need for tracking corrections
during long-exposure astrophotography.
Polaris
Fig.17: Telescope too far West
- 13 -
4. Locating Astronomical Objects
Now that your telescope is fully assembled and polar aligned,
you are ready to begin observations.
Note that although the above assembly and polar alignment
procedures may seem quite tedious—particularly if the LX10 is
your
first
serious
telescope—in
approximate polar alignment (accurate enough for visual
observing) will quickly become routine. Once set, the latitude
angle of the equatorial wedge need never be changed, unless
you move your observing site a considerable distance in
latitude, perhaps 150 miles or more.
For the beginning amateur astronomer, the simplest method of
locating objects in the night sky—and an excellent way to learn
how to operate your telescope—is to look at a celestial object
you can clearly see with your own eyes.
Find the desired object in the viewfinder, center the object in
the viewfinder's crosshairs, then observe through the main
telescope's eyepiece and adjust the focus knob until the image
is clear and sharp. With the motor drive turned on, observe how
the telescope tracks, or follows, the object as it arcs across the
sky. Turn the motor drive off for a few seconds, and note how
rapidly the objects move through the field of view.
The position of celestial objects changes over the course of the
year, so you should obtain a star chart—such as the Meade
Star Charts, available from your Meade dealer—or refer to the
monthly star charts presented in astronomy magazines, such
as Sky & Telescope and Astronomy.
With these aids and with a little experience at the controls of the
LX10, you will soon be exploring the surface of the Moon, the
planets of our Solar System and the incredible assortment of
star clusters, galaxies, and nebulae that lie beyond.
Polaris
Fig.18: Telescope aligned too low
Polaris
Fig.19: Telescope aligned too high
fact,
assembly
and
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