[M_Six]

The 2x TC does slow AF a bit. I bought a Canon grip for it, but it won't be here until Tuesday. I'm hoping the extra battery helps a bit. Still, there is clearly a focus issue with even static objects. I'll put the USB dock to work this week and dial it in. I can walk over to the football field and have a ready-made focus scale to figure out if it's front or back focusing.

DC, those hummer pics I got in Colorado were with the 2x TC, but on my 5D MkIII body. They were pretty sharp even with a hefty crop. But the Siggy was tuned to that body. Now I need to re-tune it to the 7D MkII, which I'd like to be my dedicated birding and sports rig.