• R.A. Limits (For equatorial mounts only):
Sets the limits that the telescope can slew
or track in Right Ascension (R .A .) before
stopping . The slew limits are represented in
degrees and by default set to 0°, the position
of the telescope when the counterweight bar
is extended out horizontally . However, the slew
limits can be customized depending on your
needs . For example, if you are using CCD
imaging equipment that has cables that are not
long enough to move with the telescope as it
slews across the sky, you can adjust the slew
limit on the side of the mount that is restricted
by the cables, and command the mount to
stop slewing before it reaches this point . To
set the R .A . slew limit select the following:
- R.A. East Limit: Enter a number between
+40° to -20° to define the slew limit when
the tube is on the east side of the mount .
- R.A. West Limit: Enter a number between
+40° to -20° to define the slew limit when
the tube is on the west side of the mount .
- Disable Limits: Disables any pre-defined
values that have been entered and allows
the mount to track the maximum amount
past the Meridian (i .e ., -20° on both sides) .
If you are imaging an object across the
Meridian, Disable Limits allows the mount
to continue tracking until the mechanical
limit of your mount is reached .
GoTo Approach: Lets you define the direction
that the telescope will approach when slewing to
an object . This allows you to minimize the effects
of backlash when slewing from object to object .
Just like with Direction Buttons, setting GoTo
Approach to positive will make the telescope
approach an object from the same direction as
tracking (west) for azimuth and counterclockwise
in declination . Declination GoTo approach will only
apply while the telescope tube is on one side of the
Meridian . Once the tube passes over to the other
side of the Meridian, the GoTo approach will need
to be reversed .
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To change the GoTo approach direction, simply
choose GoTo Approach from the Scope Setup
menu, select either Altitude or Azimuth approach,
choose positive or negative and press ENTER .
Guide Rates: Sets the R . A . and Dec autoguide
rate to a percentage of sidereal speed, from 0%
to 99% . This is helpful when calibrating your
telescope to a CCD autoguider for long exposure
astroimaging . Note: Most autoguiders work best
between 50% to 99% .
Direction Buttons: The direction a star moves in
the eyepiece varies depending on the accessories
being used . This feature changes the direction that
the star moves in the eyepiece when a particular
arrow button is pressed . To reverse the logic of the
direction buttons, press the ENTER once to select
Azm (Azimuth), and twice to select Alt (Altitude),
then scroll UP/DOWN to toggle Normal or
Reverse . Directions will only be reversed for
motor speeds 1-6 .
Rates 1-6 match the direction you would normally see
in the eyepiece when used with a telescope equipped
with a 90º mirror star diagonal . Pressing LEFT
corresponds to the star moving left in the eyepiece .
Rates 7-9 match the direction you would normally
see in a StarPointer finder, other non-magnifying
finder, or correct-orientation optical finder .
Backlash Compensation: All mechanical gears
have a certain amount of backlash or play between
the gears . The Backlash Compensation feature
rewinds the motors just enough to eliminate the
play between gears . The amount of compensation
needed depends on the slewing rate selected;
the slower the slewing rate the longer it will take
to observe the star appear to move in the eyepiece
due to backlash . There are two numerical values for
each axis, positive and negative:
- Positive is the amount of compensation applied
when you press the button in order to get the
gears moving quickly without a long pause .