"Rear focus"

In my last thread regarding my focusing issues with the 7D, Keith Anderson and Ron Bielefeld both recommended setting up the camera so that the AF is controlled by a button on the rear of the camera (probably the AF-ON button). In AI Servo, holding the button down allows the camera to track moving subjects, while letting go stops the focus where it is for a static subject (and allows you to recompose).

I'm looking forward to trying it. I had set things up so that the button on the end of the lens would switch AI Servo to One-shot, but that button is not very convenient to use.

If you do have your camera set up to rear focus, do you have metering and AF start tied to the rear button? Or do you have AF tied to the rear button and metering still on the shutter button?

And is there anything specific that makes you prefer having the button on the rear set to activate the focus (AF-start) as opposed to keeping the focus activation tied to the shutter button and using the button on the rear to stop the AF (AF off or AF stop)?

Thanks for any tips,

Brian

The main reason I don't like AF tied to the shutter button is that very often I want to focus, then wait for the right moment (people or animals mainly). So using the half-press of the shutter button to AF can be annoying since it has to be held there to maintain focus. With the AF button on a rear button, I can just hit it fully and focus however often I want without the annoyance of holding the half-press.

The first function I set on my Canon cameras is to disable AF from the shutter button and assign it to the * button. I benefit from controlling the shutter and exposure functions from two separate areas.
You'll get used to focusing with your thumb in no time. David has already outlkined the advantages for you.