Celestron 11074-XLT Скачать руководство пользователя

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Object

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:

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.

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.

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.

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