« on: July 12, 2014, 08:49:37 PM »
Have you tried it on kids? It couldn't keep up with mine...
I have no problem with any critter moving towards me or away. I use center point AI servo.
Like the 5DII before it, it does a decent job at tracking subjects moving across the frame, like the bighorns in your excellent image. Where the 5DII and 6D fail are when a subject is moving toward or away from the camera (away is worse). I just processed a burst sequence taken with my 1D X and 70-200/2.8L IS II of a gymnast running straight at me and vaulting from springboard onto the pad (which I was standing behind). All 26 shots in the burst are in crisp focus (lighting was pretty poor, shots were at 1/800 s, f/3.2, ISO 12800). The 7D would have gotten many of the shots in focus (but they'd have been unusable due to the ISO noise or the motion blur with a slower shutter speed. The noise from the 6D would have been acceptable, but after the first couple of frames, most of the shots would have been backfocused (and I'd have had far fewer shots, of course).
The 7D was the worst Canon DSLR I have owned. It was widely regarded as a "wildlife" lens, yet most big wildlife is crepuscular in nature, a time when the 7D falls flat. I used my 7D and the 6D in that bighorn series, and the 7D failed. Many, many out of focus shots riddled with noise. Something about even light just played haywire with the copy I had when combined with telephotos.
I'm not surprised at the 1DX results. Awesome camera.
While not the best photos, here are a couple examples of my 6D with a 300 prime and quick animals (much quicker than children). Very low sunset light, too. I've also attached the corresponding 100% crops.