Zamieszczone przez http://forums.dpreview.com/forums/readflat.asp?forum=1032&thread=30095710
AF sucks in movie mode. You have 3 AF options: quick view, live view & face detect. Quick view focuses upon activation and then doesn't focus again (from what I can tell). Live view allows you to press the AF-ON button and focus but it's slow and hunts and doesn't follow focus of subject unless you keep AF-ON pressed. Finally there's face detect, which works well until the person looks down or sideways, etc. and then it can't detect it's a face anymore and you lose focus.
Zamieszczone przez http://forums.dpreview.com/forums/readflat.asp?forum=1032&thread=30099091
The speed of AF in these modes may seem slow to the average viewer if it is performed while recording a movie.