Celestron CGE800 Telescope 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
A
ZM POSITIV
E
A
ZM NEGATIV
E
A
LT POSITIV
E
A
LT NEGATIV
E
ANTI-BACKLASH
A
LTMAX IN LIST
A
LTMIN IN LIS
T
FILTER LIMITS
A
ZM BUTTONS
A
LT BUTTONS
DIRECTION BUTTONS
A
ZM APPROAC
H
A
LT APPROAC
H
GOTO APPROACH
A
ZM RATE
A
LT RATE
AUTOGUIDE RATES
CONE VALUE
DEC SWITCH
RA SWITCH
MOUNT SETTINGS
SCOPE SETUP