Orion SynScan GoTo, Инструкция по эксплуатации

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star. Now use the direction keys to center it in the
telescope’s eyepiece and then press ENTER.
Aligning the 2nd Star
1. If the first alignment star is not a planet, the LCD
screen will display “Choose 2nd Star”; other wise, it will
display “Choose 1st Star.”
2. Scroll through the list using the Scroll keys and
refer to the appropriate star chart in the back of this
manual to choose a second alignment star. Ideally,
you want this star to be about 60 degrees (i.e., about
six fist-widths held at arm’s length) away from the first
alignment star in azimuth, and preferably at roughly
the same altitude. The more distance between the two
alignment stars, the better accuracy the alignment will
produce. Once you’ve selected a second alignment
star, press ENTER. The mount will now automatically
slew to the selected star, which should land in or near
the field of view of your finder scope.
3. After the mount stops, the hand controller will give a
long beep and display “Use dir. keys to center object.”
After you’ve centered it in the finder scope and then in
the telescope’s eyepiece, press ENTER.
• If the first alignment star was not a planet, the SynScan
hand controller will now display “Align ment Successful.”
Press ENTER to complete the alignment process.
• If the first alignment star was a planet, the SynScan hand
controller will display “Choose 2nd Star.” Repeat from Step
2 to complete the alignment process.
• If the message “Alignment Failed” displays, it usually
means the star positions do not correspond with the
location and date/time information input during setup.
Please check your user initialization settings before starting
again.
Cancellation During Alignment Process
1. While the mount is slewing during the alignment, you
may press the ESC key to stop the mount. The hand
controller screen will display “Mount stopped. Press
any key…”
2. Press any key and the SynScan hand controller will
ask you to select another align ment star.
3. Press the ESC key again, the LCD screen will display
“Exit Alignment? 1) YES 2) NO.” Press key 1 to exit
the alignment process; press key 2 to go back to
choose an alignment star.
2-Star Alignment
To perform the 2-star alignment, follow the same steps
described for the Brightest Star alignment, except that the
hand controller will not prompt you to select a directional
region for a bright star. Instead, you’ll be presented with a list
of stars available in your current sky to choose from, for each
of the two alignment stars.
3.5 Tips for improving alignment accuracy
Eyepiece
• Use a reticle eyepiece to ensure accurate centering of your
alignment objects. If a reticle eyepiece is not available,
try to use an eyepiece with longer focal length to yield a
smaller FOV. You can also try de-focusing the star image to
obtain a large star disk in the FOV. Centering the star disk
in the FOV is easier than centering a pinpoint star, in the
absence of a reticle eyepiece.
• During the alignment process, avoid changing or rotating
the eyepiece and the diagonal (if one is used).
Mechanical Backlash
All mounts have some amount of mechanical backlash on both
axes. To avoid introducing align ment error from backlash, keep
the following rules in mind:
• When centering an alignment star in the eyepiece, the
operation should always end by using the UP and RIGHT
direction keys to move the axes.
• If there is overshoot when centering an alignment star in the
eyepiece with UP and RIGHT keys, use the LEFT or DOWN
keys to pull the star back to the edge of the FOV and then
use the RIGHT and UP keys to center the star again.
Alignment Star Selection
The choice of alignment stars can also impact the alignment
accuracy. Please refer to earlier parts of
Section 3 on sug-
gestions for choosing alignment stars for various mounts and
alignment methods.
3.6 Comparison of alignment Methods
(Equatorial Mount/Mode)
1-Star Alignment
Advantage: Quickest alignment.
Preconditions:
• An accurate polar alignment for the mount.
• Small cone error in the telescope-mount setup.
• If the cone error is large, there will be noticeable offset
in the R.A. when the SynScan hand controller locates
an object that is:
• On the other side of the meridian from the
alignment star.
• Deviated significantly in declination from the
alignment star.
Rules for choosing an alignment star:
• Choose an alignment star with smaller declination. It will
help to obtain higher resolu tion in R.A. movement in the
telescope’s eyepiece.
• If there is cone error in the telescope-mount setup or if you
are unsure about it, choose an alignment star that is close
to the object(s) to be observed.
2-Star Alignment
Advantage: For visual observing, the mount does not need to
be polar-aligned accurately.