A bit more explanation on the sample shot. The reason the spark plug is not in focus is that your DOF is really thin. Folks are possibly also thinking of the DOF as a purely front-to-back dimension, but it's a distance from the focal plane, in other words from the sensor. The top of the spark plug is much closer to the sensor.
This is exactly what I'd expect to see from a fully functioning D7000 with reasonable capture technique.
_____ Brian... a bicoastal Nikonian and Team Member
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