That's a great shot Andrew. Noticed it is f/8. Manual focus? Or does AF work at f/8 with an extender?
It was taken with the 1.4x, not the 2x 
With the 2x, there's no AF - it not like it's working but slow - it just doesn't work at all so you've got to use manual focus.
I was trying aperture priority for once on the 1DX to get some DOF on the bird. Previous stuff on the 1D4 has been on shutter priority at high speed to try and freeze the bird but in lower light it opens up the aperture and ups the ISO - not good on both counts 







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