Originally posted by reh321 Yes, he was reviewing a K-70.
Those of us who are aware of these issues need to point them out. The K-70 will be kitted with the 15-135 DC lens, so that is the lens which should be used by reviewers, and we need to point that out any time the issue arises.
18-135. 15-135 would be fantastic, but it doesn't exist. Also couting K70 is entry level, I think most are going to buy it with a cheaper kit but where you are right is that at least there I find it only body only or with 18-135. Maybe Ricoh hope many will buy the kit or people know enough to choose another lens. I don't know. What I can say is all the friend that I have that brought a K30 back in time brought it with the 18-55 and wanted a nice price. They would not go for a 18-135 kit, even if that would be arguably a better choice.
Back on topic, I don't think DA50 poor performance comes from the lack of DC, I think it is more the lack of contrast wide open that require more advanced AF to work. This work on K3, not on K70. Without changing the lens and changing the body one often get nice improvement. My 50-135 improved a lot with K3 too and it is SDM... Many also reported improvements with K1.
Both the lens and the body count and on that test both were soso.
For the 18-135, I never heard of a body where it didn't AF fast and clean. While we could expect all Pentax DSLR in live view to really depend on a nice in lens motor to work, the K70 is the body, that in theory thanks to its on sensor PDAF should be able to be as fast in LV as using OVF with all lenses, including screw drive. The many mirrorless bodies out there have shown that you can have indeed very fast contrast AF, without even PDAF onboard with lenses designed for it.
The hardware seems to be there at least on the sensor, but we seems to lack the refinments on the algorithms and potentially, the hardware to make that software fast. But honestly I am not even sure of the sensor. Sure it has on board PDAF... But I think Panasonic, Olympus or Fuji tweak their sensor design too for AF. We don't know much detail of the K70 sensor. We just know LV AF is still slow.
As for review, I'd really hope a camera review could be as independant as possible of the lens. It would make sense to test a body on a selection of lenses. On Pentax K70, that should include a few kit lenses people are likely to buy (so including 18-135, DA50 and 18-55) and also a recent high end one or 2, maybe the DFA70-200...