Celestron 11074-XLT, Instruction Manual

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pause when pressing the button, go with the higher value for positive, but use a lower value for negative. CPC will remember these
values and use them each time it is turned on until they are changed.
Slew Limits – Sets the limits in altitude that the telescope can slew without displaying a warning message. By default the slew limits are
set to 0º to 90º and will only display a warning message if an object is below the horizon. However, the slew limits can be customized
depending on your needs. For example, if you have certain photographic accessories attached to your telescope preventing it from
pointing straight-up, you can set the maximum altitude limit to read 80º, thus preventing the telescope from pointing to any objects that
are greater than 80º in altitude without warning.
Slew limits are applied relative to the base of the mount not the actual horizon. So when setting the slew limits when using
the telescope on an equatorial wedge remember that a minimum slew limit of 0° would prevent the telescope from slewing
down past the celestial equator not the horizon. To set the slew limit so that the telescope will slew to the horizon while on a
wedge, you must set the minimum slew limit to equal your latitude minus 90°.
Filter Limits – When an alignment is complete, the CPC automatically knows which celestial objects are above the horizon. As a result,
when scrolling through the database lists (or selecting the Tour function), the CPC hand control will display only those objects that are
known to be above the horizon when you are observing. You can customize the object database by selecting altitude limits that are
appropriate for your location and situation. For example, if you are observing from a mountainous location where the horizon is
partially obscured, you can set your minimum altitude limit to read +20º. This will make sure that the hand control only displays objects
that are higher in altitude than 20º. If you manually enter an object that is below the horizon using the numeric keypad, the hand control
will display a warning message before slewing to the object.
If you want to explore the entire object database, set the maximum altitude limit to 90º and the minimum limit to –90º. This will display
every object in the database lists regardless of whether it is visible in the sky from your location.
Direction Buttons – The direction a star moves in the eyepiece varies depending on the accessories being used. This can create
confusion when guiding on a star using an off-axis guider versus a straight through guide scope. To compensate for this, the direction of
the drive control keys can be changed. To reverse the button logic of the hand control, press the MENU button and select
Direction
Buttons from the Utilities menu. Use the Up/Down arrow keys (10) to select either the azimuth (left and right) or altitude (up and
down) button direction and press ENTER. Pressing ENTER again will reverse the direction of the hand control buttons from their
current state. Direction Buttons will only change the eyepiece rates (rate 1-6) and will not affect the slew rates (rate 7-9).
Goto Approach - lets the user define the direction that the telescope will approach when slewing to an object. This allows the user the
ability to minimize the effects of backlash For example, if your telescope is back heavy from using heavy optical or photographic
accessories attached to the back, you would want to set your altitude approach to the negative direction. This would ensure that the
telescope always approaches an object from the opposite direction as the load pulling on the scope. Similarly, if using the CPC polar
aligned on a wedge, you would want to set the azimuth approach to the direction that allows the scope to compensate for different load
level on the motors and gears when pointing in different parts of the sky.
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.
Autoguide Rate – Allows the user to set an autoguide rate as a percentage of sidereal rate. This is helpful when calibrating your
telescope to a CCD autoguider for long exposure photography.
Cordwrap - – Cord wrap safeguards against the telescope slewing more than 360º in azimuth and wrapping accessory cables around the
base of the telescope. This is useful when autoguiding or any time that cables are plugged into the base of the telescope. By default, the
cord wrap feature is turned off when the telescope is aligned in altazimuth and turn on when aligned on a wedge.
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Scrolling through the MENU (9) options will also provide access to several advanced utility functions within the CPC such as; Periodic
Error Correction, Hibernate as well as many others.
GPS On/Off - Allows you to turn off the GPS module. When aligning the telescope, the CPC still receives information, such as current
time, from the GPS. If you want to use the CPC database to find the coordinates of a celestial object for a future date you would need to
turn the GPS module off in order to manually enter a date and time other than the present.
Lights Control – This feature allows you to turn off both the red key pad light and LCD display for daytime use to conserve power and
to help preserve your night vision.
Observing
Tip!
Helpful
Hint