Yeah, that is an option on the higher-than-entry-level Canons
It's called "Back-button focusing" in case you're curious, and it gets hard to go back to "normal" focusing methods once you get used to it.
Seriously though, set yourself on Tv, dial in to 1/1000 and set ISO to Auto and then use ONE of the focus points that gets you the best composition... For this kind of stuff you need to be in control of where the camera focuses, and not be left to let the camera decide what it thinks is important. Having the camera take care of ISO and Aperture for you is pretty much a no-brainer type setup that lets you focus on what you want to shoot and that way you're not fighting with the camera.
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