Is there any focus issues with the 5Dii? I was thinking about getting one for the HD video but didn't think the focus would be able to keep up to the action.
Depends what you mean by issues? If you plan on pointing it and expecting it to auto focus like a camcorder then you will probably be disappointed. While it does auto focus it is limited. Manual focus is the way to go on this camera in video mode but does take some getting used to. Now having said that if you want total creative expression with great use of DOF captured in all its beauty at 30fps on a full frame 35mm sensor then by all means pick one up.
Here is what is on canon`s site about focusing in video mode on the 5d mark II.
I love the camera
Focusing in Movie Mode
Focusing is a powerful creative tool in both still and moving images: Along with composition, movement, and lighting, focus helps to manipulate your viewers' eyes to the most important element of the frame.
It is possible to focus a Canon EF lens manually or automatically while capturing a movie with the EOS 5D Mark II camera. For example, when the 5D Mark II is set for Live Mode AF or Face Detection Live Mode AF in Live View, it is possible to autofocus the lens before or during a movie clip by pressing the camera’s AF ON button. However, we recommend focusing before the movie begins for the following reasons:
* The speed of AF in these modes may seem slow to the average viewer if it is performed while recording a movie.
*
Live Mode AF with or without Face Detection is a locking type of autofocus; it cannot track a subject moving towards or away from the camera.
* Depending on the lighting conditions, there may be a change in exposure level while AF is being performed.
* If you are using the camera’s internal microphone, it will pick up the sound of the lens’s focusing motor while AF is being performed, resulting in unwanted audible clicking noise.
Therefore, from an aesthetic perspective, you may find it more practical to autofocus the lens before recording begins. Of course, remember that it’s also possible to focus manually at any time. This can come in handy when you want total control of the lens' speed and timing -- for example, to transition from a sharply focused image to a blurred one (or vice versa); to follow a moving subject; or to rack focus between different planes in your shot (i.e. foreground to background).
The EOS 5D Mark II’s 3-inch, 920,000 dot Clear View LCD screen makes it easy to focus and compose images with its brilliant, sharp display. Additionally, it’s possible to superimpose fine or coarse grids as a compositional aid, and it’s also possible to superimpose a semitransparent border for 16:9 or 4:3 aspect ratios.
You can read the whole article here
http://www.usa.canon.com/dlc/controller?act=GetArticleAct&articleID=2186
