Re: SNR Measurements for CCD vs CMOS sensors

Posted by karenacollins on Aug 18, 2022; 6:48am
URL: http://astroimagej.170.s1.nabble.com/SNR-Measurements-for-CCD-vs-CMOS-sensors-tp1973p1985.html

Since Noise has a factor of roughly 1/SQRT(Gain), with gain as defined above, when gain is increased, noise will decrease (with all other factors remaining the same). Since Noise is in the denominator of S/N, S/N should generally increase when gain is increased (with everything else remaining the same).

That's because when gain, as defined above, is increased, it implies you had more electrons that caused the ADU values in the aperture (since it is fixed in your test), which is F* in the equation. Since a higher gain implies that more electrons resulted in the measured ADUs, that means that more photons were incident on the detector, which would mean lower Poisson noise, and thus a higher signal to noise ratio.

Karen