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Old 12-01-2009, 12:48 PM
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Peter Ward
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Quote:
Originally Posted by Dennis View Post
From the authors website:

"If the angular velocity of the RA shaft deviates from the prescribed (sidereal or King Rate) velocity value, it accelerates or delays telescope's driving clock. .........

Dennis
The flaw in this system is it simply isn't looking at deviations at the imaging sensor level.

Perhaps they use a direct coupled encoder, or they couple the system via intermediate gears, either way there are still eccentricity, indexing and periodic errors.

The only way these can be accounted for is to accurately measure deviations against the sky, not the RA shaft.
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