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Note:
The Fine Azimuth Adjustment Knobs (9), Fig. 1, are
generally only utilized during the precise polar alignment
procedure described in the instructions accompanying the #812
Polar Alignment Finder,
Locating North by using Polaris, the North Star, is adequate for
the purposes discussed above. Polaris can be found in relation
to the Big Dipper by projecting a line from the so-called 'pointer
Stars" of the Big Dipper (see Fig. 8). For southern hemisphere
alignment, locate south by using the faint star Sigma Octans
(the South Star).
0.i...
i
Little Dipper\
i
^
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Polaris
I
I
Big Dipper
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O' ■
Cassiopeia
|"r^8; Locating Polaris,
Using a Polar Aligned Telescope
Once the telescope is polar aligned (as described on page 5),
the R.A. Slow-Motion Control is the only conirol needed to keep
a celestial object in the field of view of the telescope.
1.
To center a celestial object within a polar aligned
telescope, unlock the Dec and R.A. lock levers (2) and (3).
Fig. 6. Do not move the tripod or adjust the latitude angle
when centering an object in the telescope, as this will
destroy the polar alignment.
2.
Once a celestial object has been centered in the
telescope, lock the Dec and R.A. lock levers (2) and (3),
Fig. 6. Then, slowly turn the R.A. Slow-Motion Control
(4), Fig. 6, while observing through the telescope, to
keep the celestial object within the telescope's field of
view.
Precise Polar Alignment Procedures
For astrophotography or other advanced applications, the
optional #812 Polar Alignment Finder can be used to
dramatically increase the accuracy of the polar alignment
process.
As a result, the accuracy of the setting circles
increases, making faint objects easier to find. See OPTIONAL
ACCESSORIES, below.
Setting Circles
Setting circles permit the location of lain! celestial objects not
easily found by direct visual observation. Locate the Dec setting
circle (1), Fig. 6, and the R.A. Setting Circle (5), Fig. 6, on the
LXD 500 Equatorial Mount, To use the setting circles, follow this
procedure:
1,
Using a star atlas or star chart, look up the celestial
coordinates (Right Ascension and Declination) ot an easy-
to-tind object, such as a bright star,
2,
With (he telescope polar aligned, center the cnosen ongbl
object in the telescope's field of view.
3,
Manually turn Ihe R.A. selling circle (5), Fig 6, to read the
R.A of Ihe bright object. This setting circle is sligntly stilt to
ti 1,.,^
ar.r'irl.anlal m^M/tirT>nnl r,f tha r'irrla itiiiar'. tr.,a
circle by placing a hand on either side of the mount. Grasp
the setting circle with the thumb and forefinger of each
hand and rotate the circle until the R.A, coordinate of the
object is correctly indicated by the R.A. pointer on the
mount.
4. Manually rotate the Dec Setting Circle (1), Fig. 6. until the
Declination coordinate of the object is correctly indicated
by the Dec pointer on the mount,
5-
The setting circles are now calibrated.
To locate a faint
Object using the setting circles, determine the desired
object's celestial coordinates from a star chart or
astronomy computer program. Unlock the Dec lock lever
(2), Fig. 6, and the R.A. lock lever (3), Fig. 6, and move the
telescope in R.A. and Dec until the setting circles read the
R.A. and Dec of Ihe desired objecl. Then, lock the Dec and
R.A. lock levers. If this procedure is performed carefully,
the faint object will be in the (ield of view ol a low-power
eyepiece.
Note: Once the Dec circle is accurately calibrated, il need never
be louched again, even on subsequent observing sessions.
The R.A. circle, however, must be re-calibraled to the R.A. of a
known object each time the circles are used to find an object,
which might be several times in one observing session.
OPTIONAL ACCESSORIES
An assortment ol professional Meade accessories is available
for the Model LXD 500 Equatorial Mount,
#812 Polar Alignment Viewfinder
The LXD 500 Equatorial Mount has provision in its polar axis tor
Ihe addition of the #812 Polar Alignment Viewfinder.
This
borescope device facilitates quick, precise polar atignment of
Ihe telescope. An internal reticle contains an etched clock-like
scale.
A separate Polar Reference Circle shows the correct
position of the North Star on Ihe Finder's reticle scale at any
time and day of Ihe year.
#1701 Single-Axis Drive System
The addition of the #1701 Single-Axis Drive System allows a
polar aligned telescope to track on a desired
object
automatically, keeping the object in the field of view without
manual adjustments in R.A, Add the #1705 Declination Motor
to the #1701 for full dual-axis drive capabilities.
#1702 Dual-Axis Drive System
Attaching the #1702 Dual-Axis Drive System to the LXD 500
Equatorial Mount provides quartz-controlled sidereal-rate
tracking in R.A,, plus full dual-axis drive capabilily at any of four
photo-guide or microslew speeds: 2x. 8x, 16x, or 32x.
#1705 Declination Motor
The #1701 Single-Axis Drive System becomes a complete, fully
functioning dual-axis drive system with Ihe addition of the #1705
Declination Motor.
#1708 Computer Drive System
The #1708 Computer Drive System includes live high-torque,
dual-axis drive speeds including the fast slewing speed of 4° per
second: and locates and centers in the field over 64.300 objects,
automatically.
Quartz-locked sidereal-rate tracking; GO TO
capabilily and digital readouts on both telescope
axe.s
are
just
some of Ihe many otner
features
available
when the #1708
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