This is the most maligned focus point selection system. Everybody says how useless it is. It’s the default mode for Canon. Can’t be that bad if Canon sets it as the default, unless Canon wanted to sabotage the millions of dollars spent developing the 7D. The focusing area cover over 60% of the viewfinder with very few gaps.

  • In One-Shot AF Mode, the Canon 7D will focus on the closest focus point with enough contrast.
  • In AI Servo AF Mode, the Canon 7D will start with the selected point, by default the center focus point and will track the subject over the 19 points area.

The Good

  • Easy and simple to use
  • Single moving subject moving across the frame in AI Servo auto-focus
  • Great with wide angle lens and shoot overhead in One-Shot auto-focus
  • Great for birds in flight against sky, sporting event with long tele… Much easier than tracking with the center point.
  • In AI Servo auto-focus, the subject can move out of the center.

The Bad

  • In the One-Shot AF mode, multiple subjects.
  • In the One-Shot AF mode, the camera decides what to focus on, usually the closest.
  • In the One-Shot AF mode, bad for focusing through busy “front grounds”.
  • According to June who uses a Nikon D3, the automatic 19 points select focus point is similar to the size and the behavior to the famed Nikon CAM 3500 Auto-area AF mode.