Originally posted by audiobomber What makes you say that? At f8, 28mm and 1/120s, it should be sharp.
This may in fact be the problem: I have noticed that in photographs taken at shutter speeds of 1/100, 1/120, and all the way up until 1/200 show distinct motion blur. With the SR switched OFF this does not occur, so it is clearly a problem with the SR overcompensating at these shutter speeds, for whatever reason. Pentax should be able to fix this via firmware.
That aside, I also had a lot of problems with softness when I first got my K-x. Since then, I´ve found that I simply need to be more careful with my shooting technique, keep the shutter speeds between 1/25 and 1/80 or 1/250 to 1/6000, and use the smallest practical aperture with the kit lens. It does, undeniably, seem more finicky than previous cameras I´ve owned, but when you get it right the results are very, very satisfying. I feel like it may be sharper on the pixel level than my K20D was.
Also, buying a sharper lens might help. The DA-L kit lens that came with my K-x definitely seems inferior to the DA II version I had before, even though they´re supposed to be optically identical. I picked up an M 50mm f1.7 for $35 and it´s very crisp at all apertures on the K-x (again, provided good technique).