Celestron 11074-XLT, Instruction Manual

Page: 22 / 61

22
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 CPC 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 .
2. Choose Database to select the object that you want to observe from any of the database catalogs listed
3. Choose RA/DEC to enter a set of celestial coordinates that you wish to slew to.
4. 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.
5. Use the direction buttons to carefully center the alignment star in the eyepiece.
Press ENTER to slew to the desired object.
To store a set of coordinates (R.A./Dec) permanently into the CPC database, save it as a
User Defined Object as described above.
S S c c o o p p e e S S e e t t u u p p F F e e a a t t u u r r e e s s
Setup Time-Site - Allows the user to customize the CPC 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
CPC'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.
Positive backlash compensation is applied when the mount changes its direction of
movement from backwards to forwards. Similarly, negative backlash compensation is
applied when the mount changes its direction of movement from forwards to backwards.
When tracking is enabled, the mount will be moving in one or both axes in either the
positive or negative direction, so backlash compensation will always be applied when a
direction button is released and the direction moved is opposite to the direction of travel.
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
Helpful
Hint
MENU
SCOPE SETUP
UTILITIES
SETUP TIME-SITE
ANTI-BACKLASH
SLEW LIMITS
FILTER LIMITS
DIRECTION BUTTONS
GOTO APPROACH
AUTOGUIDE RATE
GPS ON/OFF
LIGHTS CONTROL
FACTORY SETTING
VERSION
GET AXIS POSITION
CORD WRAP
GOTO AXIS POSITION
HIBERNATE
SUN MENU
SCROLLING MENU
CALIBRATE GOTO
SET MOUNT POSITION
PEC
DISPLAY LEVEL
KEYPAD LEVEL
PLAYBACK
RECORD
ALT POSITIVE
ALT NEGATIVE
AZM POSITIVE
AZM NEGATIVE
ALT APPROACH
AZM APPROACH
DEC RATE
RA RATE
ON
OFF