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Old 07-09-2014, 08:57 PM
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peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: SE Tasmania
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Quote:
Originally Posted by Amaranthus View Post
This 10-frame stack is useful, as I noted, for getting a better 'averaged' estimate of the centroid, compared to a single long WDM exposure, and also avoids guidestar bloat etc. Once can control the FWHM of the guidestar nicely by playing with the WDM exposure time (and gain, if necessary), without mucking about with the actual guide pulse.
Barry,

I thought PHD effectively sums the 10 individual exposures rather than averaging them. How do you quantify the stack of 10 is better than a single longer exposure in terms of estimating the centroid? I believe the main consideration in terms of centroid estimation was to ensure you are not trying to guide on a saturated star hence the use of the star profile graph.

Cheers,

Peter
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