However, the site's founder, Dave Etchells, had occasion to use the Pentax K20D while shooting an outdoor sporting event and had a terrible time, prompting him to write this brief report:
Autofocus report, by Dave Etchells
In our testing, the K20D revealed itself to be a very capable camera, delivering good image quality overall, with excellent fine detail, and it performed quite well in the lab. Outside the lab, we found that its autofocus performance was severely lacking in a sports shooting environment. While it's not part of our normal test procedure, I had the occasion to take the K20D and the fairly high-end Pentax 200mm f/2.8 ED IF SDM SMC DA* prime telephoto lens to shoot one of my son's rugby games. It turned out to be an exercise in frustration, despite the fact that Pentax's SDM ultrasonic motor should have made the lens pretty fast to focus. Shot after shot, the camera just would not find the proper focal point, despite my being careful to use the center focus point and keep it on the player I was most interested in. Even when the action didn't seem terribly fast, the camera frequently misfocused, to the point that only about 50% of my shots were usable. In frustration, I switched to my Nikon D80, which had only its 18-135mm kit lens mounted. This didn't give me the reach I really wanted, but the improvement in AF performance was little short of startling: Suddenly, 90-95% of my shots were sharply focused.
Bottom line, while the K20D is an excellent camera in many respects, we really can't recommend it for capturing fast-paced action.