In SNR graphs for Pentax K-30 and Pentax K5 there is something I do not get.
For ISO after 1600 the SNR doesn't really decrease. Moreover comparing with Nikon D3200, we can clearly see that until ISO 1600 the sensors behave almost the same, after that things change. Is there an explanation for that? Is there any processing done to reduce the noise?
(graph from DxO)