Just got a D3100 with 16-85mm Nikkor. So far still imaging has been awesome but the video, specifically the focusing is giving me fits. No matter what mode I use the focus seems like it is always searching or just stops (doesn't focus). I've been used to taking video with cheap point n shoot cameras with no issues at all. i never heard the camera focusing, images were always in focus. Now, with the D3100:

1)I hear the focus mechanism in the video
2)When I change subject distance the camera doesn't refocus easily, sometimes not at all. doesn't matter which focus mode I use.

In short, I am disappointed in the video function so far. Am I doing something wrong? Any suggestions?

I guess they haven't worked out the bugs yet, anywho, have you tried taking video and when you move around you press the shutter halfway as if you were taking a picture? either that or you can do what I do for my D5000, get really friggin good with the manual focus. oh btw how good is that 16-85?

Congratulations on the purchase btw

I have the same problem. Very disappointing when the cheaper
point and shoots video is excellent without the constant
focusing. I'm not sure what to day since being able to take
video and still shots with the same camera is very important
to me. I thought I was doing something wrong. The noise and
the constant going in and out of focus is very distracting to
the video. I was expecting much more with HD and constant
focus. If anyone can help with suggestions, it would be
appreciated. Thanks!

I have used the Video with Auto shooting mode on a tripod indoors with a 28-70 lens.
Usually the camera will lock right on the person in the center.
Otherwise, I use the AF-On button (reprogrammed AE-L AF-L) to p refocus on them.
The little square lights up and if they do not move off the screen, the camera will track them.
You only have to pan the camera when they move further.
I have not even tried face priority AF yet.

I do not hear the focus mechanism.
Perhaps, FullAutomatic puts the camera in silent shutter mode.
The mono mic is surprisingly better than the D90 of even the 5D2.

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