This banal photo shows something very odd.
I focused on the poppy (orange) at center bottom. Observe how focus slices diagonally through the frame, roughly speaking from the upper left down through the poppy to lower right: the plane of focus is skewed. This cannot be reconciled with the reality of the situation.
This also explains some bizarre sharpness results I saw with other field shots, where there was blurring where there should have been none, and sharpness where it should not have been.
Click for a larger image (very large, your browser might scale it).
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