Originally posted by Parallax Comparing images side-by-side on the Imaging Resource site, I only noticed the noise being a touch greater from the K-3 above ISO 6400; however, they were noticeably sharper. At 6400 and below I couldn't convince myself that there was any difference.
I noticed that with the Imaging Resource site too, when comparing K-5IIs and K-3 DNGs. The K-3 was noisier, although only ISOs above 6400 were a worry.
But when I did
my own side-by-side comparisons with my own K-5IIs and K-3, the differences largely disappeared. The differences may be because of slightly difference automatic exposure between these cameras.
I don't expect the K-3 to have significantly better high-ISO noise characteristics, but I'm not worried that that it is significantly worse. So I've pretty well dismissed this is as "no significance change" for my own purposes. (And of course in nearly every other respect the K-3 is better).