Quote:
Originally Posted by Peter Ward
But, there's the rub, the mean flux can vary enormously.
With a bright lunar image the S/N is so high as to make the amplitude of the stacked signal + noise almost 1:1 compared to an exposure equal to the total stack time....
All a bit moot really.
Take lots of frames.
Make sure they have more than just noise.
|
I disagree.
I took a moon pic at 250th/second and did not calibrate or use noise reduction and the image showed no noise.
Now I could have taken 20 pics and stacked them and still improved the SNR
noise = square root of mean photon flux.
This is disregarding camera induced noise which can be calibrated out.
Now I agree that the flux can vary enormously, but then so does the noise.
If you point a dslr at the sky from a light polluted suburban sky and expose for 30 seconds you sure will get more signal than noise .Unless you using a pin hole camera of course then you probably wouldnt get any signal
.
Great discussing these points with you
Regards steve
