I made a couple of quick AF tracking tests with the GH2 the other day, and I thought some of you who have wondered how it works might like to see them.
High school basketball game, GH2, 14-140, ISO 2500. I was shooting stills at ISO6400 and f2.8, but I brought the GH2 along and took a few minutes of video to see how the camera worked in these conditions. I used 24P, 50th sec and ISO2500. I think the 30 fps, or 720/60P would be better for this much motion, but the AF seemed to do a good job, and the video is amazingly clean at ISO 2500.
http://www.vimeo.com/18138884
Running dogs tax an AF system more than any subject I know. I have not tried birds in flight, so that may be a rival, but no human sports even come close to presenting the AF tracking challenge that fast moving dogs present. That said, the greatest difficultly comes when they are running straight at the camera, because their heads are moving all over the frame, and if their eyes are not in focus, the image is unusable. Here there is more lateral movement, but they are still moving toward and away from the camera.
Dogs playing, 720/60P, 14-140 mm, ISO 800,
http://www.vimeo.com/18137872
That was very impressive Bill. This is a big deal to me in wanting the GH2. The dogs were constantly moving and the camera seemed to follow them perfectly.