Keep your eyes on the prize
My hummer buddy has been pretty accomodating this morning. He knows I won't hurt him, just annoy the heck out of him at times. So, I decided to swap cameras and mount my 70-200L f4 IS onto my a7r instead of 5D3. Naturally, he decided to perch in the bush where the light is different but I was undeterred.
Here he is keeping his eyes on the feeder in the upper left corner (I purposely left a bit of red blur there). I used manual focus with magnify assist on this shot.