I'm not a Duck ?

Armed with my new toys [1DN and 70-200 2.8 IS] I went out to shoot the obligatory duck this morning

I've lots to learn, having come from using a P&S. Can someone tell me why the background is patchy in the coloured part on the right ? I'm guessing its the ISO or having a 1.4x extender on [didnt take it off as it was pouring with rain] ? Is the odd shading on the neck due to the same thing ? If I squint, it all looks quite nice

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a nice very sharp shot, i dont see the neck as odd shading the background is how i would exspect it to be owing to a narrow dof it sort of magnyfies the out of focus parts in your shot it does not look at its best only because you have quite high contrast in the background if you had moved just a little to the left the head would have been in a better less contrasty area .
Rob.

The sharpness is excellent and good colour too.

Thanks for the replies - maybe I've been staring at it too long and worrying about nothing. Will take comments on board and try again after work tomorrow [weather forecast is better tomorrow]. Hopefully these little guys will be there again having their swimming lessons

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