I did not think about this until reading these recent posts but one thing to consider is that the 80-400 is Nikons first VR lens and still uses that original VR mechanism.

I have a few VR lenses and the implementation of VR on the 80-400 is kind of clunky and not quit as effective compared to the others.

I remember quit a few instances of seeing the image sharp in the viewfinder and then going out of focus upon release of the shutter (as noted by Keith above) resulting in a poor image. This behavior may be contributing to some of the issues you have been seeing with when using this lens.

Dave
Quad Cities, USA
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