Celestron CGE800 User Manual

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