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[filmscanners] RE: Newish Digital Tech
Hi Robert...
> Yep, shot noise = photon noise. And yes it's sqrt(S). So when the
> signal is
> twice as big then the noise only increases by sqrt(2) which improves the
> SNR.
Err....aaaa... Hum. You have to add the noise floor to it though. For a
noise floor of 25:
# of Electrons Noise
10 25+sqrt(10) = ~28
20 25+sqrt(20) = ~29.5
100 25+sqrt(100) = ~35
200 25+sqrt(200) = ~39
1000 25+sqrt(1000) = ~57
2000 25+sqrt(2000) = ~166
10000 25+sqrt(10000) = ~135
20000 25+sqrt(20000) = ~166
I’m not seeing a sqrt(2) in noise increase for a doubling of electrons
here...but clearly the SNR is better as the signal gets larger, for one
reason because the noise floor is increasingly less of the overall signal,
so of course that happens.
Austin
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