A few days ago i recieved my 1Dx mkII.
Sunday i had the possibility to test it out at a soccer game.
Since i wanted to test the Auto focus as much ass possible.
I decided to use it together with my "old" 400/2,8L IS USM and the 1,4X III teleconverter. With the "old" 1Dx, that combination are quite "slow" compared to not adding the teleconverter.
What i can say for now. Is that the auto focus with the 1Dx mkII are very impressive. It's blazing fast. And extremely accurate. Considering that this camera has 14 FPS (frames per second). It's even more impressive.
I don't want to get into all the technical stuff here. But the more FPS, the harder to get Auto focus to be accurate. The major reason for this is that the AF-sensor gets its information while the mirror is down. What the engineers that work at Canon has managed to do is truly impressive.
The first image below are taken with a 1Dx and a 70-200/2,8L IS II USM. The last with the 1Dx mkII and the 400/2,8L IS USM (without TC). All the rest with the combination 1Dx mkII, 400/2,8L IS USM and TC 1,4X III.
“An inexhaustible good nature is one of the most precious gifts of heaven, spreading itself like oil over the troubled sea of thought, and keeping the mind smooth and equable in the roughest weather.”
― Washington Irving