I was NOT so lucky with my hummingbird shot. I looked out the kitchen window this morning and saw a hummingbird zigging and zagging about. I had the 1DX and 24-105L lens in my kitchen, but nothing else. And, it was POURING outside. So I aimed and fired out the kitchen window, thru the glass, and you have to admit that despite the mediocre image, this was a true verification of the AF system on the 1D X.