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Old 12-01-2015, 07:32 PM
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Paul Haese
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Quote:
Originally Posted by alpal View Post
Paul,
Hi Paul,
Isn't there such a thing as sky noise? - the atmosphere glows.
There is thermal noise & shot noise etc

If the signal is below that noise you won't see any signal.

What is the signal from a dark area of open space?
The Hubble Deep field would tell us that at our resolution
it is a the sum of light from all those 1000's of galaxys.
In which case we can't resolve them & they just turn into a smudge of background noise.

I believe the correct term is signal to noise ratio.

cheers
Allan
Point taken. Though noise being a random thing stacking methods will hide the noise pretty well.
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