DxOMark Tonal Range Specification

DSPographer wrote:

I think the definition of signal for a DXOmark SNR is just the mean value of the count at the illumination needed for that mean value. Their noise definition includes read noise, shot noise, and PRNU. So, their full SNR plot plots the SNR at many mean count values: from an SNR of 0 dB to full count. The SNR 18% value reported on the second tab plot is just the SNR from the full SNR plot at 18% of full scale count for each ISO.