I shoot a lot of sports with a pair of 7D Mark II and an assortment of lenses.
My "policy" with sports is to always use as few AF points as possible... usually single point (not "spot"), occasionally the 4 or 8 point expansion, and rarely the small zone. When I'm using single point it's on me to make sure the camera is focusing right where I want it to focus. If I miss, it misses.
When shooting with single point, fast action when there's no time to change AF point, sometimes it's necessary to zoom out a little to allow some room to crop later. I walk a thin line with this... wanting to fill my viewfinder with the subject as much as possible for the best image quality... but at the same time often needing to crop just a little to get the composition I want.
Any time you use more than one point you are leaving it up to the camera to figure out where it's supposed to focus. Often it will choose correctly.... But sometimes it won't!
The two expansion modes are a little different. They start with the center point, only expand to the adjacent points if the camera senses the subject has moved away from the center point and onto one of those adjacent points. I'll usually use the 4-point mode when I have a pretty good idea where the subject will be going, but they are moving fast enough that I may struggle to keep up with a single point. I'll use 8-point when I am less certain where the fast moving subject will be going. Different sports call for different setups.
In small zone the camera can choose any of the available AF points to use, both when starting AF and during continuous focusing.
I mostly only use single point "spot" when out shooting wildlife for fun. It uses a smaller than usual AF point, which can be helpful trying to photograph a bird or animal through tree branches or tall grass.
I can't recall the last time I used the large zone mode and don't think I've ever used "all points".
I use back button focusing... Learned the benefits of it around 20 years ago with film cameras and have used it with every camera since. If I ever got a camera that didn't have means of doing BBF, my thumb wouldn't know what to do! 😎😁
BBF allows me to use AI Servo almost exclusively. The only time I might use One Shot is when shooting a landscape or a posed portrait or maybe a macro shot (though I usually do those with manual focus).
I've tweaked a few of the autofocus related settings that are available on the 7DII, but won't go into most of those here. However, I will mention that I've set my 7DIIs up so that the joystick can always be used to move AF points around and so that clicking the joystick instantly returns the AF to the center. This makes it possible for me to make AF point changes while keeping the camera to my eye and my eye on the subject(s).
The 7DII's control layout is great. It allows fast, direct access to many things. The AF controls, in particular, are right where they should be on the camera (and on it's matching battery grip).
It has nothing to do with the questions about focusing... But I don't see any problem with using Tv if that's your preference. Some sports shooters like to lock in their shutter speed. Personally I do use Av far more often, but I keep an eye on my shutter speeds and adjust the ISO if needed to get fast enough shutter speed for whatever action I'm shooting. I want to control the aperture and depth of field.
More often recently I've been using M with Auto ISO. That allows me to lock in both aperture and shutter speed. The 7D Mark II has well-implemented Auto ISO (the original 7D didn't). The only thing I dislike is that with M + Auto ISO it's a bit fiddly to use Exposure Compensation. It has to be done with the menu or Q screen (usually the latter). There's no direct dial to use for E.C. when the camera's exposure mode is M + Auto ISO.
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
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Danny
