Pre-focus vs tracking: when and how to use each technique

Getting sharp photos of moving subjects is a tricky skill to master, but knowing which technique to use for which subject will help improve your hit-rate…

There are two main ways to focus on moving subjects: you can either use the Servo or continuous autofocus mode, so that the camera ‘tracks’ the subject by continuously adjusting the focus automatically, or you can use manual focus, and wait until your subject reaches a point you’ve pre-focused on in advance.

Which you should use depends to some extent on the type of subject and movement you’re shooting.

Generally speaking you should use continuous autofocus for subjects where the movement is unpredictable, such as birds in flight, animals running or team sports; and manual focus (also known as pre-focusing) for subjects where the movement is more predictable, or regular.

Pre-focus vs tracking – how to capture moving subjects with confidence

01 Select the focus mode

These modes will enable the camera to automatically adjust the focus as the subject moves, as long as you keep the shutter release half-pressed.

With the focusing mode set, you should also set the drive mode to Continuous shooting, to allow you to shoot in bursts to maximise the chances of getting sharp results.

For subjects where you can’t easily predict the direction or speed of the movement, you first need to select the AI Servo (Canon) or Continuous (Nikon) focus mode.

02 Select the AF point

If you’re using a long telephoto lens with a maximum aperture of f/5.6 or smaller, or if you’re shooting in low light, you will get better results by selecting the central point rather than the outer ones, as on most cameras this is more sensitive and accurate.

To give you some control over where in the frame the camera will focus, you need to select the single-point autofocus mode, and then select the focus point where you are going to position your subject in the frame.

03 Track the subject

The most important skill you need to master is keeping the AF point positioned over the subject, to enable the camera to track it as it moves around.

Try to frame your subject as soon as it comes into view, and then follow its movement as smoothly as possible.

While following the subject, you can shoot in short bursts when the focusing has locked-on.

This takes plenty of time to master, so don’t be too disappointed if you don’t get it right first time, especially with subjects such as birds flying, or fast-moving sports.

04 Pre-focusing

If you can predict where your subject will be, such as with a car on a racetrack, you can autofocus on pre-determined point, and then switch your lens to manual focus to lock it off.

Then, without altering the focus, you can either follow your subject through your viewfinder and fire away as it passes this point, or compose your shot in advance and wait for the subject to appear in your viewfinder.

With the camera in continuous drive mode, you can take a short burst of two or three shots just as the subject reaches the point that you’ve pre-focused on.