Celestron CGE1100, CGE925, CGE800, CGE1400 manual Precise GoTo, Scope Setup Features

AZM APPROACH

ALT APPROACH

AUTOGUIDE RATES

AZM RATE

ALT RATE

MOUNT SETTINGS

CONE VALUE

DEC SWITCH

RA SWITCH

Named Object or Messier catalogs, the hand control will let you know that the Ring Nebula (M57) is approximately 6° from your current position. Searching the Double Star catalog will reveal that Epsilon Lyrae is only 1° away from Vega. To use the Identify feature:

•Press the Menu button and select the Identify option.

•Use the Up/Down scroll keys to select the catalog that you would like to search.

•Press ENTER to begin the search.

Note: Some of the databases contain thousands of objects, and can therefore take a minute or two to return the closest object.

Precise GoTo

The CGE has a precise goto function that can assist in finding extremely faint objects and centering objects closer to the center of the field of view for astrophotography and CCD imaging. Precise Goto automatically searches out the closest bright star to the desired object and asks the user to carefully center it in the eyepiece. The hand control then calculates the small difference between its goto position and its centered position. Using this offset, the telescope will then slew to the desired object with enhanced accuracy. To use Precise Goto:

1.	Press the MENU button and use the Up/Down keys to select Precise Goto.	SCOPE SETUP
•	Choose Database to select the object that you want to observe from any of the		SETUP TIME-SITE
	database catalogs listed
•	Choose RA/DEC to enter a set of celestial coordinates that you wish to slew to.		ANTI-BACKLASH
2.	Once the desired object is selected, the hand control will search out and display			AZM POSITIVE
	the closest bright star to your desired object. Press ENTER to slew to the bright
				AZM NEGATIVE
	alignment star.			ALT POSITIVE
3.	Use the direction buttons to carefully center the alignment star in the eyepiece.			ALT NEGATIVE
4.	Press ENTER to slew to the desired object.		FILTER LIMITS
				ALTMAX IN LIST
Scope Setup Features				ALTMIN IN LIST
			DIRECTION BUTTONS
Setup Time-Site- Allows the user to customize the CGE display by changing time and					AZM BUTTONS
					ALT BUTTONS
location parameters (such as time zone and daylight savings).
			GOTO APPROACH

Anti-backlash– – All mechanical gears have a certain amount of backlash or play between the gears. This play is evident by how long it takes for a star to move in the eyepiece when the hand control arrow buttons are pressed (especially when changing directions). The CGE's anti-backlash features allows the user to compensate for backlash by inputting a value which quickly 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 for the star to appear to move in the eyepiece. There are two 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. You will need to experiment with different values (from 0-99); a value between 20 and 50 is usually best for most visual observing, whereas a higher value may be necessary for photographic guiding.

To set the anti-backlash value, scroll down to the anti-backlashoption and press ENTER. While viewing an object in the eyepiece, observe the responsiveness of each of the four arrow 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 immediate 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

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