cheineck Loc: Hobe Sound, FL

I forgot if I sent this... Gigapixel with PS and cropped.

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Strodav Loc: Houston, Tx

As someone has already posted there are parts of all the images that are tack sharp, but not necessarily the subject (although the deer came out nice and sharp). My best guess is your camera / lens combination is back focused just a bit. I'd set up a focus target (can get one off the internet) with a ruler at a 30 degree angle (high behind the focus target and low in front of the focus target with the middle of the ruler at the focus target) and shoot it raw, AF-S (still), aperture wide open, relatively low ISO, say, < 400, use a tripod and a remote release or the camera's timer. Adjust your shutter speed so the ruler is exposed correctly. Take shots at different zoom factors with the ruler taking up about 1/3 to 1/2 or your viewfinder (want to use the center of the lens). A good sequence is a couple of shots in Live View mode, then 3 shots in AF mode at each zoom factor you want to test. Before every shot move the manual focus ring off of focus a bit so the camera needs to refocus with every shot. Pull the images over to your computer and look at the ruler, which will tell the story.