Yeah, hard to say Michael..... I'm certainly no expert on lenses..... One idea that did just pop into mind was the choice of ISO at 800..... There is a lot of grain in the sky areas (which really can happen at any ISO) but I'm wondering if that choice of 800 introduced so much grain that you cannot get the bird sharp because of it. Took your original and tried sharpening it up a bit but I'm not sure if there is a noticable difference between this and the second postworked version?

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