Re: Deep Sky Imager II Noise Reduction

On 18 Nov 2006 08:40:11 -0800, info@xxxxxxxxxxxxxxxx wrote:

Klaus,
I know a little bit about this - Meade's software matches each light
exposure taken at a certain temperature to a "dark" exposure taken at
the same temperature. This ensures noise is minimized. Also, the CCD
chip in the DSI II has lower dark current noise than a DSI I chip.

Subtracting dark exposures does not reduce noise. In fact, they
typically increase noise. Darks are used to reduce certain types of
fixed pattern problems.

_________________________________________________

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

Relevant Pages

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