Sabaki said:
I've watched some birders take bif sequences with a 1DX and they nail at least a 90% keeper rate, which is not the same for users of the 5Diii. (Admittedly, most of the birders in my community will shoot with a 1DX or 7Dii and not the 5Diii)
When chatting to those 1DX users, they advise the following:
* The bigger battery drives the lenses quicker and more efficiently
* The dedicated ITR chip in the 1DX means tracking in AI Servo mode is just way better
Anybody agree or disagree with their above statements?
Absolutely agree with both. The battery benefit is often missed when comparing these two bodies. I have also found that auto exposure (Auto ISO in manual mode) and auto white balance are both more accurate with the 1Dx.
My needs are rather demanding. I shoot a lot of figure skating including ice shows under nothing but spotlights. The AI Servo mode is particularly challenged during rotational jumps. Keep in mind that AI Servo is a predictive algorithm where the system tracks the subject's movement to predict where the subject will be when the shutter is actually tripped. This is why it's best to start tracking a second before shooting. This algorithm is critical for burst mode when the AF system if frequently interrupted when the mirror is up.
During a rotational jump, the subject starts by skating in one direction, which is easy for the camera to track. Then the skater suddenly goes vertical and while in the air, rotates. Now whatever portion of the costume that the focus point locked on is moving up, away, then back toward the camera. With the 5D3, I often lost focus during the jump. This seemed to be hit or miss. It also often tracked without problem. By the way, during practice, skaters often wear black with no contrasting decoration -- yet another challenge for the AF system.
The 1Dx is noticeably more consistent with AF tracking during jumps. It isn't 100% and at full burst, I can still get a frame or two that isn't quite sharp. But, my keeper rate is much higher. Plus, the 12 FPS makes it possible to get a photo of a skater in mid-jump while looking in my direction. With the 5D3, I had to try to time this moment and most often missed. (The 8 FPS burst mode of the 7D was also too slow to get this moment.)
Most recently, I shot skaters during dress rehearsal (under spotlights) while I was on the ice in skates. There were a couple skaters with signature moves that I was able capture while I was moving (actually chasing the skater as they skated away from me during their element). The 1Dx/70-200 f2.8L II did a great job tracking the subject under these circumstances.