Nikon Focus areas explained
Although I predominately use the Single-point AF or Auto-area AF, you might find one of the other AF-area modes are more suited to your style of photography. Although not every camera will have all of these modes, the other potential Nikon focus areas are as follows. These explanations are based on the camera being set to the AF-C (Continuous-servo AF) mode. It is worth experimenting to see which of these modes will work for your camera and style of photography.
Single-point AF
A single focus sensor is active, and the camera will focus on whatever it falls over. The active sensor can be changed using the Multi Selector.
3D-tracking AF
Similar to Single-point AF, a single sensor is active, and the active sensor can be changed using the Multi Selector. When the shutter release is pressed, the sensor focuses, but also locks on to the subject using colour recognition and it’ll attempt to track it across the frame. It will also track the subject if you recompose. This area mode is a good replacement for single point.
Dynamic-area AF
Similar to Single-point AF, a single sensor is active, and the active sensor can be changed using the Multi Selector. Depending on the Dynamic-area AF mode selected (9, 21, 51) then the corresponding number of other sensor points around the active point (8, 20 or 50) will be used to track movement.
Group-area AF
The camera uses an active matrix of five sensors that can be moved around the frame, and will focus on the closest object to within the active focus sensors. This area won’t be much good if you’re photographing wildlife and have an animal sitting in a bush, as the sensor will focus on the bush not the animal.
Auto-area AF
Your camera tries to automatically detect the subject and focus. If AF-C is selected then it’ll track the subject.