Re: Best Webcamera for Astroimaging currently?

On Fri, 13 Feb 2009 10:27:19 -0500, "Jason Banco" <abad@xxxxxxx> wrote:

Some people
have actually achieved better results with high end peltier cooled astro CCD
cameras in poor conditions because the amount of images needed to produce a
good SN result is far less than with webcam based non-cooled CCDs.

I don't think this is true. For planetary imaging, cooled cameras
provide little or no benefit, because cooling only addresses dark
current noise, not readout noise. With the short exposures required for
planetary imaging, readout noise is effectively the only instrumental
noise source, and it is no lower with cooled cameras than with good
video cameras.

Under poor seeing, webcams and other video cameras always outperform
higher end astrocameras because they are able to collect many short
exposures, and utilize lucky imaging techniques. While I have seen
excellent planetary images made with dedicated astrocameras, those
images have, without exception, been collected under very good seeing
conditions.
_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
.

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