I agree that you need to make sure you have AFMA set for your lens. I would also recommend learning a new way to focus your shots since the 1DX has a ton of settings when it comes to auto focus and using one shot is probably not the best in many situations. I used to use one shot quite a bit, but I almost never use it now and the 1DX rewards me with about a 98% hit rate even with some very difficult shots at 85 f/1.2 or 200 f/2. That hit rate is after approximately 100K shots on my 1DX. Yes, I shoot quite a bit too.
These videos might help understand the complex auto focus system on the 1DX. I am still trying to learn what settings are best for each type of situation. Get it right and you should get killer sharp images.
If you use a tool like FoCal then you can test auto focus consistency which should help you understand what focus points are more consistent and if your lens is working properly.
Thanx for your comment. I will get going on the micro adjustments. Hopefully the 24-70 II will be better as well...
And, FoCal is only for PC
I think I have to adjust my way of working... Which sucks since I've been working this way for 9 years and never had these many problems. I shoot models. I can't stop a paid photoshoot to check every photo on the camera, nor I want to slow down. It sucks when you are reviewing the photos on the computer and you have good poses and good expressions and the photos are unusable... It makes u feel bad.
This is my first Full Frame camera and I am kind of regretting it. Basically a cropped sensor has the best part of the sensor. The other 30% is the vignetting and distortion that nobody needs.
If you look closely at the focusing points on the image, they only cover 50% of the actual center of the frame. They should spread out the points, like on the 1D IV to cover more area.
If you are trying to focus on a face, shooting a full length body, the closest focusing point will be under the neck. Unless the model is wearing a shirt that contrasts with her skin or a necklace or something that the camera can pick up as a contrasty focusing point, the photo will be out of focus. Here is a sample to illustrate my point...
I wish Canon had a cropped shooting mode like Nikon.