SKY-WATCHER EQ6, Инструкция по эксплуатации

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I
A
ccurate Polar Alignment
Generally speaking the EQ6 SkyScan
TM
produces pointing and tracking accuracies edaquate for most
visual applications. However, if higher precision is required, for example for astro-photography,
accurate polarscope alignment and "cone" error calibration may be required.
Accurate polar alignment enhances both pointing and
tracking precisions. For long exposure astro-
photographer, it is important that the telescope mount
be aligned with true North in order to precisely track
celestial objects.
In order to achieve accurate polar alignment, the reticle
in the polar scope must be centered on the optical axis
of the polar scope (see p.6 Polarscope Alignment) and
the index marker ring must be calibrated.
The Index Marker
The polarscope in combination with the RA setting circle
constitutes a circular slide rule. This slide rule is used to
calculate the hour angle of Polaris at your local time
anywhere on the planet. On a given day of the year, eg
March 30, at a given local time, eg 10:00pm, the hour
angle of Polaris is the same, anywhere on the planet.
This is an approximation, which is good to about 4
minutes of arc. The index marker represents a 'zero' for
the slide rule. If the zero is not set correctly, the
calculated hour angle will not be correct.
Unlock the RA locking knob. Rotate the telescope
around the RA axis so the reticule is as shown in Fig u.
Re-tighten the RA locking knob to lock the RA axis in
this position. In this position, Polaris is in transit - it is at
its highest point in the sky.
Unlock the RA setting circle by loosening the set screw.
Rotate the RA Circle so the pointer indicates 'zero' and
lock the RA Circle. This sets the first of two 'zeros'
required for the slide rule. Now rotate the telescope
around RA axis so the RA Circle indicates 1h 0m (Fig.u-
1). Lock the RA axis. Rotate the Date circle so October
10 is indicated (see Fig.u-2). At 1:00 AM local time, on
October 10, Polaris is in transit anywhere in the world.
Rotate the telescope around the RA axis so the RA
circle indicates 'zero' and lock the RA axis. The view
through the Pole Finder should be the same as before.
Loosen the setscrew on the index marker ring. Adjust
the index marker ring so the Date circle reads 'zero' on
the longitude indication (Fig.u-3). Secure the ring by
tightening the setscrew. This sets the second of the two
zero points.
If the reticule has been re-aligned or the index ring has
come loose, this procedure must be carried out again to
ensure accurate polar alignment.
Fig.u-1
10 10
11 11
9
8
Fig u-2
Fig.u