Now thats way too cool. I am boiling in the heat here in Cape Town and am not at work with ADSL so having to resort to 56k dial up. So needless to say I am offline while I compose my message.
Perhaps in my next life
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Firstly lets look at some of sources of noise you list.
These are largely unrelated to the photons impinging on your detector and can be removed by proper calibration. for example you mention crosstalk. This can be removed by using shielded twisted pair, coaxial cable and a suitable physical separation between the cables. Of course sigma algoithms can reduce the effect of cosmic ray hits
The correct calibration procedures will reduce the remaining noise to a minimum
You add shot noise to the list. now I understand that shot noise is poisson noise caused by the statistical variations inherent in the impinging photons.
This is the noise I am referring to for the sake of this debate.
Now I agree that the amount of signal received is proportional to the exposure time and the noise inherent to the impinging signal = square root of the mean photon flux over the integration time. I cannot see that the noise is going to exceed the signal over time because each summation adds the signal as well as adding the noise, and the noise is by definition substantially smaller than the signal over the integration time. (after all you did calibrate and apply the other subtraction algorithms to minimise the other sources of noise)
signal combined = signal raw minus signal dark.
Now I understand that my perspective is coming from compromise being that I use a dslr, a budget mount that is overloaded to say the least and a scope with fl=1520mm at prime focus. Hence I must consider all the compromise as a given. However, these issues still apply even to the Hubble which also uses track and stack to produce the stunning images which it does on a regular basis. Cant wait to see what the Webb does
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Regards
Steve
