Orion SynScan GoTo, Инструкция по эксплуатации

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The PEC training function provides a correction to reduce
the amplitude of the worm gear errors. By recording the guid-
ing actions over one full worm gear cycle, SynScan can then
“play back” those actions with each subsequent worm cycle to
compensate for drifting in the R.A. sidereal tracking caused by
periodic error.
Orion equatorial mounts feature two different types of PEC,
depending on the model of the mount. One type is soft ware-
based PEC (SPEC), which applies to Orion’s SkyView Pro
GoTo, Sirius EQ-G, and Atlas EQ-G mounts. The other type is
permanent PEC (PPEC), which comes standard with the Atlas
Pro AZ/EQ-G and HDX110 EQ-G mounts. The SynScan hand
controller detects the mount model and chooses the appropri-
ate PEC algorithm.
Note: PEC training is recommended for advanced users with
interest in long-exposure astrophotography only. Careful guid-
ing is required. Standard sidereal tracking is sufficient for
casual visual applications, and PEC training is not required.
PEC Training
For mounts that support standard, or software-based PEC,
such as the Sirius EQ-G and Atlas EQ-G, you’ll need to manu-
ally (visually) guide for at least one full worm cycle using an
illuminated reticle eyepiece capable of producing at least 300X
magnification with your telescope. For best results, the true
field of view should not exceed 10 arcminutes.
For mounts that support PPEC, such as the Atlas Pro AZ/
EQ-G and HDX110 EQ-G mounts, an autoguiding camera can
be used instead of manual guiding for the PEC training pro-
cess. In such cases, it is recommended to turn on the autogu-
ider for at least one minute before starting the PEC training
process. The total time for the PEC training of these mounts
can be as long as two cycles of the period error.
The following step-by-step procedure below describes how to
perform the PEC training function manually, using an illumi-
nated reticle eyepiece.
1. Perform an accurate polar alignment, then perform a
GoTo star alignment.
2. Then choose a star close to the celestial equator, i.e.,
with a small Dec. value (Dec. b10° and –10°).
This object will be used as the guide star. Point the
telescope toward it and start the mount tracking.
3. Rotate the reticle eyepiece in the focuser (or diagonal)
until the R.A. movement of the star (i.e., its movement
when you press the Left or Right direction button)
runs parallel to one set of the illuminated crosshairs.
Then center the star on the crosshairs of the
eyepiece’s reticle.
4. Access the menu “Utility Func.\.PEC Training” and
press the ENTER key. The screen will display “Select
Speed: 1) 0.125X 2) 0.25X.” This is the speed used to
move the star in the FOV of the telescope when you
press the Left or Right direction key on the SynScan
hand controller. Choosing a 0.125X sidereal rate is
recommended for a longer focal length telescope, and
a 0.25X sidereal rate is recommended for a shorter
focal length telescope. Press the “1” or “2” key to make
a selection and proceed to the next step.
5. The screen will display the elapsed time once the
guide speed has been selected, indicating that the
recording of the guiding actions has begun. Use the
Left and Right direction keys to con trol the mount and
keep the star centered in the reticle eyepiece until the
SynScan beeps and stops displaying the time. (If the
star drifts in declination, it doesn’t matter. PEC is only
concerned with corrections of movement in R.A.) The
total time for this training process depends on your
particular mount model, but it will be at least several
minutes. Pressing ESC will immediately stop the
recording and exit from the PEC training function.
PEC Replay
Once PEC training is completed, PEC tracking can be turned
on by accessing the menu “Setup \ Tracking \ PEC+Sidereal,”
then press the ENTER key to start the PEC replay. The
SynScan will play back the guiding corrections you made dur-
ing the PEC training cycle to compensate for the periodic error.
Notes:
• The PEC + Sidereal tracking rate will be accurate only after
at least one full cycle of PEC training is performed.
• After turning on the PEC + Sidereal replay, wait for at least
one worm cycle before taking a picture.
• To re-use the PEC data on a mount that supports SPEC,
users should “park” the tele scope before shutting off power
(refer to
Section 6.3). This stipulation does not apply to
mounts that support PPEC.
6.7 Calibrating auto-Home Offset
Some Orion equatorial mounts, such as the HDX110 EQ-G,
have an Auto-Home function that can automatically set the
mount to a standard home position after turning on the power.
The offset of the home position can be calibrated and compen-
sated with the following procedure:
1. Accurately polar-align the equatorial mount.
2. Turn off the power, then turn it on again, and then
initialize the hand controller.
3. When the SynScan hand controller displays “Auto-
Home?,” press the “1” key to execute the au to-home
process.
4. Finish the subsequent initialization steps.
5. At the end of the initialization, choose 1-star alignment
to align the mount.
6. At the end of the 1-star alignment, the hand controller
will ask “Update H.P.O? 1) No 2) Yes” (“H.P.O.” stands
for Home Position Offset).
• Press “1” to keep the original Home Position Offset.
• Press “2” to use the results obtained from the 1-star
alignment to calibrate the home position offset.