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Old 11-01-2012, 12:13 AM
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RickS (Rick)
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Quote:
Originally Posted by Terry B View Post
That doesn't make sense as the whole point of an AO unit is to overcome the effects of the seeing.
Terry,

My opinion is that an active optical system like the AO-LF (which is much simpler than observatory grade adaptive optical systems) probably corrects for polar alignment errors, mount periodic error and other physical stuff like wind pretty well. I suspect they can help to some extent with seeing, but only a limited amount. That's for two reasons: seeing can almost certainly change faster than the system can react at times and also seeing is unlikely to be consistent over the whole FOV so a simple tilt mechanism can't correct over the whole FOV (adaptive optical systems that I've read about can actually make localized changes to the shape of the primary mirror to make different corrections in different regions of the FOV).

And yes, the "Hertz" is the frequency of guide exposures and tilt adjustments per second.

Cheers,
Rick.
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