http://forums.dpreview.com/forums/readflat.asp?forum=1036&message=39288778
I am afraid that I have to agree with the OP that the ISO 6400 picture of the 5N is very close to that ISO 3200 picture of the K-5, for both the amount of visible noise and also for the amount of image details that are retained. So, it is either that Sony has improved their that 16.2MP Exmor sensor and has made a new version, or that they have improved their image processing, so that they have successfully sucked out more from the same sensor, or maybe both!
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