Originally posted by SloPhoto With motorsports, you can NOT use AF on a pentax if the car is coming twards you.
As much as I despise the pentax AF system (and love the rest of the camera), it is not its lack of focusing speed.
It is the lack of predictive focus. Even if it locks on to the front bumper when the shutter trips, in the time that the mirror has come up, the car is already past your focus point. If you want the rear bumper in focus, it works great. Not sure who would want that though.
As a previous poster mentioned, you need to revert to zone/manual focus for those shots. If the next pentax does not have predictive AF, I will buy a canon for my motorsports shots/backup camera. It would be a shame to do so, and I hope I do not have to.
WHOA! Easy there dude! Never say never! I would say you don't wanna' use the continuous mode, (sometimes you get lucky, sometimes you don't), but AF-S seems to work alright most of the time. I agree the Pentax does not have equal focusing to the Canon or Nikon brands, but most everyone knows that when they make the purchase. I am willing to forego that single issue as I love everything else about the camera, and I know I can compensate, most of the time. That being said, I do occasionally miss a great shot because the K10 couldn't focus quite fast enough.
As has been pointed out there are things you can do to help alleviate the problem. Bump your F stop up, for one. even f8 is often enough to bring your whole subject tack sharp when using AF-C.
1/500 f8 iso160 fill flash AF-C - K10, Sigma 100-300 4.0 EX DG @ 150