Quote:
Originally Posted by Merlin66
Guys,
I was referring to shot noise and shot noise only....
The quoted original para 3 doesn't say that the difference in SNR is due to the varying shot noise....later quote: "by adding many doses of read noise"
Theory is great, but what about the noise you add to your images through processing??????
Lazjen,
I'd love to help if you can explain how you currently measure the SNR in your images....what "improvements" are you looking for????
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Ken, our measure of "SNR" is the perceived graininess in an image that may be arbitrarily stretched and possibly smoothed or sharpened. There is no maths for "graininess" in this environment so we use the well developed physics of signal and noise in a linear imaging system as a surrogate - on the simple basis that, if we can get better true SNR in the underlying linear image, we will have better perceptual graininess in the pretty picture.
Using SNR theory enables us to optimise our equipment in a systematic way and relate problems in the "pretty picture" domain to the underlying physics. We do not need to measure true SNR to do this (although some of us do when pushing the limits or testing our understanding of the theory), but that doesn't invalidate the approach.