Canon autofocus systems are so easy to use and so effective that many photographers rarely switch to Manual Focus or MF (not to be confused with Manual exposure mode, denoted by M in the camera menu and on the mode dial, if your camera has one). But how do they work, and what do the different options mean?
When you use autofocus, there are a range of settings and options available, which may vary from camera to camera. For easier menu navigation and setting, all the AF settings and Custom Functions are grouped into one menu tab, so there is no need to jump into different menu areas to make changes. These are the choices on the EOS R5:
AF operation: One Shot AF (for still subjects) or AI Servo AF (for moving subjects). Some cameras have an AI Focus AF mode in which the camera chooses which of these two to use, according to the subject movement it detects. Find out more about AF operation modes.
AF method (or AF Area on some cameras):
- Face Tracking – including, in the latest cameras, bird and animal tracking. On some cameras, this appears as a separate Subject tracking menu option;
- 1-point AF – the camera focuses using a single AF point;
- Spot AF – the camera focuses using an even smaller area than 1-point AF;
- Expand AF area – there are two options here. With either, the camera focuses using a single AF point, but if it is unsure then it uses another AF point to assist, or may switch to that point instead – either the next point horizontally and vertically, or the next point diagonally as well. Both of these are effective with moving subjects, which are difficult to track with 1-point AF;
- Zone AF – uses auto selection AF within a larger area, optionally focusing on the nearest subject or using various criteria such as faces, subject motion and subject distance.
Subject to detect – on the latest cameras with Intelligent AF, this instructs the camera's AI to give priority to People, Animals, Vehicles or No Priority. On some cameras, a separate Subject tracking option must be enabled first. Find out more about AF configuration options.
Eye Detection on or off.
Touch & drag AF settings (available on selected newer cameras including the EOS M50 Mark II and EOS R System models) – see the section below about specifying the AF point.