Sky-Watcher Synscan Hand Control - Manual (Page 9)

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PART III : ALIGNMENT
Advantage: For visual observing, the mount does not need to be polar-aligned accurately.
Preconditions: Small cone error in the telescope-mount setup.
Rules for choosing alignment stars:
• The deviation in R.A. of the two alignment stars should not be too small or too close
to 12 hours; the recommended deviation is between 3 hours and 9 hours.
• If there is cone error in the telescope-mount setup or if users are not sure about it,
it is recommended to choose two alignment stars that are on the same side of the
meridian. The absolute values of the two alignment stars’ declination should better
deviate between 10 to 30 degrees.
Note: If the polar alignment of the mount is good, it is not necessary to choose “ 2-Star
alignment ” to align the mount, use the “ 1-star alignment ” instead.
Advantages:
• Good pointing accuracy; even when the telescope-mount system has cone error.
• For visual observing, the mount does not need to be accurately polar-aligned.
Preconditions: The skies of both sides of the meridian are clear of obstructions.
Rules for choosing alignment stars:
• The 3 alignment stars should be spread out on both sides of the meridian.
• For the two alignment star on the same side of the meridian, the deviation in their
R.A. should be greater than 3 hours, and the absolute value of the difference of the
two alignment stars’ declination should be between 10 to 30 degrees.
( 10° < |Dec1 – Dec2| < 30°)
• If there is cone error in the telescope-mount setup or users are not sure about it,
avoid the situation that all 3 alignment stars have small declination (close to the ce-
lestial equator).
Note: If users are sure that there is no (or very small) cone error in the telescope-mount
system, then it is not necessary to choose the “ 3-star alignment ” to align the mount. Use
“ 1-star alignment ” or “ 2-star alignment ” instead.
The “ Brightest Star Alignment ” is designed for entry level users who cannot identify stars in
the night sky, and the “ 2-Star alignment ” is for users who know the names of the stars in
the night sky. Both alignment methods provide the same level of precision.
Rules for choosing alignment stars:
• It is recommended that the altitude of the two alignment stars are between 15 and 60
degrees and the deviation of altitude is between 10 and 30 degrees.
• The azimuth deviation of the two alignment stars can be between 45 and 135 de-
grees, it is best to be close to 90 degrees.
2. Equatorial Mount with 2-Star Alignment:
3. Equatorial Mount with 3-Star Alignment:
4. Alt-azimuth Mount:
PART IV : SYNSCAN MENU TREE
Date
Time
Observ. Site
Daylight Saving
Alignment
Backlash
Tracking
Auto Guide Speed
#
Elevation Limit ^
Auxiliary. Encoder +
Sync. Encoder
Handset Setting
Factory Setting
Alignment Stars
1-Star Align. #
2-Star Align.
3-Star Align.
#
Brightest Star ^
Polar Align.
# *
SETUP MODE
Show Position
Show Information
Identify
Park Scope
PAE
GPS
PC Direct Mode
Polar Scope LED
# +
PEC Training # +
Camera Control # +
Set Star Name
Adv. Filter
Sort By
Time
Version
Power Voltage
Polaris Positiuon
Polar Align. Error
#
UTILITY FUNC. OBJECT LIST
NGC Catalog
IC Catalog
Messier Catalog
Caldwell Catalog
SAO Catalog
Double Star
Variable Star
User Object
Deep Sky Tour
Recall Object
New Object
PAE Correction
Clear PAE Data
Home Position
Current Pos.
Custom Pos.
Named Star
Solar System
The SynScan hand control uses menu tree to organize its various functions. The following
table shows the menu tree:
4.1 Menu Structure
Note:
# Applicable to Equatorial mounts
^ Applicable to Alt-azimuth mounts
* Only available after 2-star or 3-star alignment is performed
+ Applicable only to certain types of mounts and motor controllers.