The new crop of DSLRs that shoot video have really piqued my interest, but one thing I haven't seen much on is how autofocus works (if it does) when shooting HD video. It's not a dealbreaker or anything, I'd just like some info. The ability to change lenses (shared with my 40D) makes this a very tempting piece of equipment.

The Canon DSLRs have only a slow contrast push focus.

But on the other hand i knew no professional camera with a big sensor (APS-C or FF) that have a continous autofocus - so that is not a "problem" of DSLR.


Daniel

The Panasonic GH1 does continuous autofocus, at a sufficient speed, while recording. It can even be set to track faces. Of course, the sensor is slightly smaller than APS-C.

The GH1 is not a DSLR and because it does NOT use a mirror, the camera is able to autofocus while shooting.

Many DSLR's since the Live-view days have been able to do _slow_ contrast based AF. There have been some optimizations in firmware updates, but it's still slow.

Panasonic made it a point to work on making it faster, hence AF on their m43 bodies are much faster than the Olympus EP series.