Meade LX200-ACF Telescope User Manual


 
(Note that it does not prevent you from performing a manual slew past this limit.)
This is useful when you have a camera or other peripheral attached to the
telescope—you can prevent it from striking the telescope base. 90 (straight up) is
the maximum value that can be entered.
W
Mount Lower Limit: Allows you enter a number from 0 to 90 that sets a lower
limit as to how far the optical tube can swing downward during a programmed
slew. (Note that it does not prevent you from performing a manual slew past this
limit). This is useful when you have a large optical tube (12" model) or have a
dewshield attached to the telescope—you can prevent it from striking the
telescope base. -90 (straight down) is the maximum value that can be entered.
W
Park Position: For permanently mounted telescopes only. After aligning your
telescope, select this menu and power down the telescope. The alignment
settings—level, North, time, alignment stars—are stored in AutoStar II’s memory
and are remembered after you power off the telescope. When you power on the
telescope, “Automatic Alignment” displays after the start up routine. Press MODE
(do not press ENTER). The telescope remembers its alignment and you can
continue viewing or performing other operations without aligning the telescope
again.
Park Position provides two options. Use Current Position uses the last position
set by the user. Use Default Position levels telescope and points it North.
W
Calibrate Home: For permanently mounted telescopes only. After aligning your
telescope, select this menu and the alignment settings—level, North, time,
alignment stars—are stored in AutoStar II’s memory and are remembered after
you power off the telescope. You can enable AutoStar II to retrieve and
automatically align your telescope using these settings the next time you power
up by choosing the Align on Home menu. See
ALIGN ON HOME
, page 29, for
more information.
Note: This method is not as precise as
PARK POSITION
(see
above).
W Anti-Backlash: This option allows you to change the backlash along either the
R.A. and the Dec. axes by entering a number from 0% to 199%. This sets the
backlash in the way the Arrow keys move the telescope along an axis. If you enter
a value near 199%, telescope responds more quickly as you hold down an A r r o w
k e y. If you enter a value near 0%, it takes longer for the tube to respond as you
hold down an Arrow key. Experiment with this option: Try changing the values until
the motion of the telescope (while holding down an Arrow key) feels comfortable
to you.
W
Train Drive: All telescopes have a certain amount of “backlash” (looseness in the
interplay of gears). This menu allows you to compensate for the backlash in the
the Altitude and Azimuth motors—which helps locate objects with more precision.
W
Calibrate Sensors: This menu allows you to improve your telescope’s pointing
accuracy to alignment stars. It calibrates to correct slight mechanical
misalignment due to transport, vibration, or aging. It is recommended that
calibration be performed once on a new telescope after the user initially
assembles it.
When this menu is selected, the telescope slews to Polaris. AutoStar II then
prompts you to center Polaris and to press ENTER. AutoStar II uses the position
of Polaris to fine tune the position of North and also detects level for the base of
the telescope.
W
Tracking Rate: Changes the speed at which the telescope tracks targets in
the sky.
a. Sidereal: The default setting for AutoStar II; sidereal rate is the standard rate
at which stars move from East to West across the sky due to the rotation of
the Earth.
b. Lunar: Choose this option to properly track the Moon over long observing
sessions.
c. Custom: Allows entry of user-defined tracking rates.
W
Guiding Rate: Allows you to change the base slew speed, 1x. Enter a
percentage of the speed (less than 100%) and press ENTER. This function may
be useful in guiding the telescope during CCD and long-exposure photography.
See
SLEW SPEEDS
, page 18, for more information.
N o t e :
Custom Tracking Rate
allows you to enter values
from -999 (stands for -
99.9%) to 999 (stand for
+99.9%). The lower the
n u m b e r, the slower the rate;
the higher the number the
faster the rate. If you enter
-999, the telescope will
move so slow as to appear
to be stopped. If you enter
999, the telescope will be
moving at approximately
twice the tracking rate.
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