Changing the Autofocus Button on Canon Digital SLRs
A while ago, I noticed that my friend Jonathan seemed to have a special setup on his Canon 5d—he wasn’t using the shutter button to auto-focus his subjects. He had decoupled the auto-focus from the shutter button and instead used a button on the back of the camera. I tried it; I loved it.
What’s the point of doing this? It allows you to keep shooting regardless of what’s going on with the focus motor. I find that it’s really helpful if you’re shooting with a reasonable depth of field and the subjects are moving around a lot (parties, street photography, people in general). It’s a much faster manual workflow and it takes only a short period of shooting before it feels very natural.
To configure this is easy, but I don’t recommend your camera manual—it’s very obtuse language. Instead, check out: Canon Digital Learning Center - Back-Button Auto Focus Explained. On a 5d Mark II, my FN IV Custom Functions (Operations / Others) have the following settings: #1 is set to 3 and #2 is set to 1.
Happy shooting.
