Re: Alternatives to Drift Alignment?

[EMAIL PROTECTED] (Brian Tung) wrote in news:[EMAIL PROTECTED]:

> John Oliver wrote:
>> My assumption was that this was for a portable scope being setup for 
>> a single imaging session.  Of course a permanent scope can get 
>> better than that but in that case why worry about how long the 
>> measurement will take?
> 
> No, my assumption is a portable scope, too.  I just find it interesting
> that one can't expect to get much better than 5-arcminute accuracy 
using
> drift alignment.  I would have expected it to be better than that--
hence
> my comment about slow convergence.  It surely would be slow if you 
wanted
> much better than 5-arcminute accuracy.
> 
> Incidentally, this is just for my own edification.  I don't do any
> imaging.
> 
> Brian Tung <[EMAIL PROTECTED]>
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You get rid of the residual error by using a guide scope or self guiding 
CCD chip.

L.