I found some more information about the K-01's internals. Kimio Tanaka mentions in his blog that the low pass filter is different to that of the K-5. Incidentally, Kimio Tanaka is the photographer who interviewed the Pentax R&D guy last year in Digital Camera Magazine.
http://thisistanaka.blog66.fc2.com/entry/685/
found through
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Actually, he writes so conversationally that computer translation is not very helpful, but here are the main points.
- Although his first impression of the design was that it is a bit odd, he actually has no complaints about the design and he is glad that it is different to all the other mirrorless cameras out there.
- The low pass filter has just one layer, rather than the usual two. This is what gives it superior sharpness and contrast.
- He generally seems to be a fan of the camera.
I have been really been impressed by the pixel-level sharpness of the shots I've taken. I'm amazed that my old lenses are capable of such detail. However, my point of comparison is the K20D, not the K-5.