Originally Posted by mattdm 
I'm going to be the first to say it, but please don't shoot me. The high-ISO pictures totally have clear vertical pattern noise. We're never going to hear the end of it on the forums.
I wouldn't be concerned about VPN yet. First, contrary to many opinions, it is in fact largely a result of under-exposure and little else. Not pretty... but can be generally beeliminated with spot on exposure.
I think overall that these images, probably unenhanced, show very good dynamic range. The skies are clearly NOT blown out and detail still seems to be rendered in the shadows. Typical of Pentax the images look about 1/2 to 1 stop underexposed. That said, high key sand will have a propensity for underexposing the image via meter bias.
Then again, the PROS there should have made said compensation on the fly
Color saturation and contrast is simply wonderful. What one should expect from DA* lenses. Yes?
Stephen