Starting Automatic Slewing - Vixen SPHINX SXD Instruction Manual

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Hint 13 In a pair of reference points for alignment (= a pair alignment), two reference
points that are located opposite each other will make pointing accuracy worse. Avoid
choosing reference points in succession that are more than 90 degrees apart from each
other.
Hint 14 If you wish to use reference points that are more than 90 degrees apart, first
make a pair alignment with reference points that are located within 90 degrees of each
other. Then make a second pair alignment in the same way, but the third reference point
can be more than 90 degrees from a former (second) reference point. Pair alignments
made across the whole sky will keep the pointing accuracy high in every direction.
Hint 15 Choosing a reference point near the zenith will make pointing accuracy worse.
Due to the nature of equatorial mounts, you won't be able to improve the pointing accuracy
near the zenith even if you complete a pair alignment perfectly. Use a low power eyepiece
to search for a celestial object in this case.
Hint 16 A variety of celestial objects can be used for reference points; the Moon, planets,
nebulae and star clusters. However, using a reference star (fixed star) is recommended as
it may be difficult to determine the center of extended celestial objects like nebulae or star
clusters.

Starting Automatic Slewing

Automatic slewing becomes available as soon as a two point alignment (the first pair
alignment) is completed. Proceed to automatic slewing when you've finished the
alignment. Choose celestial objects that you are interested in observing.
Hint 17 Up to 19 alignment points may be used to raise slewing accuracy.
The following is an example for slewing to the planetary nebulaM57 (the Ring Nebula) in the
constellation Lyra (the Lyre).
- Zoom the star chart out on the screen by pressing the Zoom- key to find the target
constellation in a large area of the sky.
- In CHART MODE, locate your target (hereafter M57) in Lyra with the keys.
Zoom the star chart in (along the way) by pressing the Zoom+ key to center M57 on the
crosshairs with the keys.
- Continue zooming in further while centering M57 in the crosshairs with the
keys.