Celestron StarSense AutoAlign, Руководство пользователя

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If you attempt to slew to an object that is outside
of your slew limits, a warning message will appear
to confirm that you want to proceed with slewing .
Default slew limits are 10º-70º .
• 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
pass 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 .
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 .
- Negative is the amount of compensation
applied when you release the button, winding
the motors back in the other direction to
resume tracking .
To adjust, press ENTER . While viewing an object in
the eyepiece, observe the responsiveness of each of
the four direction buttons . Note which directions you
see a pause in the star movement after the button
has been pressed . Working one axis at a time, adjust
the backlash settings high enough to cause imme-
diate movement without resulting in a pronounced
jump when pressing or releasing the button . Now,
enter the same values for both positive and negative
directions . If you notice a jump when releasing the
button but setting the values lower results in a pause
when pressing the button, use the higher value for
positive, but use the lower value for negative . The
telescope will remember these values and use them
each time it is turned on until they are changed .
Custom Rate 9: Customizes the speed at which
the mount slews to a target . Press ENTER to view
the current rate and highest possible rate . The value
is displayed in degrees per second . Press ENTER
to get to the value you want to edit and enter the
desired value . Then press ENTER again to confirm .
PEC (Periodic Error Correction for Equatorial
Mounts): Periodic Error Correction, or PEC for
short, is a system built into some telescope mounts
that improves the tracking accuracy of the drive by
reducing the number of user corrections needed to
keep a guide star centered in the eyepiece . PEC
is designed to improve imaging quality by reducing
the amplitude of the worm errors .
Refer to your telescope instruction manual for
details about Periodic Error Correction .
Set Axis Position References the alignment if the
clutches are disengaged . For instance, you might
use this feature if you needed to rebalance the
mount after having completed an alignment . To set
the mount position, simply slew to a bright star in
the named star list and select Set Axis Position .
The hand control will sync on the star by asking
you to center the star in the eyepiece and pressing
the Align button . Once synced on the star, you are
free to manually move the mount in both axes in
order to rebalance . When you are ready to slew the
telescope to your next object, manually return the
tube to the same bright star and carefully center it
in the eyepiece . Using this tool will invalidate the
PEC index .
Home Position: Some telescopes have index
marks or switch positions . Home Position will return
the telescope to this location .
Hibernate: Hibernate allows the telescope to be
completely powered down and retain its alignment
when turned back on . This not only saves power,
but is ideal for those that have their telescope
permanently mounted or leave their telescope in
one location for long periods of time . To place your
telescope in Hibernate mode:
1. Select Hibernate from the Telescope Menu .
2. Move the telescope to a desired position and
press ENTER .
3. Power off the telescope . Remember to never
move your telescope while in Hibernate mode .
Once the telescope is powered on again, the