Re: Deep Sky Imager II Noise Reduction


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

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 - nice web site! You're obviously more knowledgeable about CCD
imaging than me, but what you wrote above surprises me.
If I take an image and don't apply a dark, the image is full of random
bright pixels (noise). After I apply a dark, all the noise is gone.
Why do you say subtracting darks does not reduce noise?

Thanks,
Paul.

.

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