I have just received the final firmware v1.00 and wanted to make available some samples shot at ISO 400-6400 in tungsten light (2900/2950 K, using Auto WB). Shot with the kit lens and AF focussing onto the SD card in the center.
This is a preliminary article and my evaluation of noise is pending. Also, the subject is not ideal (colors missing, no gray card). I was in a hurry. The ball's surface has a subtle texture looking like noise but not being noise (in iso 400)! So, this may be used to compare denoising artifacts.
The camera was set to "natural" (default is "bright") and default settings otherwise (i.e., sharpness -1, NR medium, NR start iso800).
The images are here (out of camera or Lightroom standard settings):
K-7 Tungsten high iso noise
And the DNG raw files are here:
Preliminary test, firmware is final but the sensor in my preproduction camera is said by Pentax to be different from the final one!
This is very warm tungsten (below 3000 Kelvin). In daylight, the noise would be much less. Also, ISO6400 is not a fully advertized feature.