I've mostly been using my XF100 for shooting weddings and slower paced events, but a have been doing some freelance work for a university football team and have had some problems with focusing in the fast paced environment. All the shooting is done at night with the aperture wide open with no gain under the lights, which looks pretty good. The problem I've been having is this: If there is a 40 yard pass completed when i zoom out and attempt to refocus slightly it COMPLETELY blows out the focus. The focus goes way to far, probably 3-4 feet instead of the 50-60 feet that i need. When focusing without changing the focal length it is completely fine. I have had to train myself to strictly zoom, then focus which takes more time then I would like.

Has anyone else experienced this problem? I thought maybe there was something wrong with my technique but a can recreate the situation again and again. Any thoughts on how to cure this problem?

Thanks!
Derek

Anyone own an XF100 and can turn it on and try it? Trying zooming in while rotating the focus ring clockwise and see if it reacts the same way mine does?

I just tried this, and am not sure I fully understand.

I zoomed back fairly wide, then manually focused on something only 3 feet away. I then aimed at something about 30 feet away and tried to focus as I zoomed in on the more distant target.

Since I almost never use manual focus - the depth of field on the camera and the excellent autofocus work fine for my needs - I'm not practiced at this, but at times it seemed like as I zoomed in and focused from 3 feet to 30 feet the focus seemed to suddenly jump and it was very easy to overshoot the focus.

But it seems to me more like my ability is lacking rather than a camera glitch. I was shocked by how little I had to turn the zoom ring to get the longer zoom shot in focus. Or am I totally misunderstanding what you're talking about?

It sounds like your XF is doing the same thing mine is. I dont believe its is a lack of skill as i am used to focusing on a shallow DOF dslr as well as the XF, just hadn't experienced this until the high paced sporting event came up. I have found that focusing while zooming multiplies the focus ring distance 2-3x. Very annoying!