Subject tracking autofocus

A focus mode where the camera continually refocuses on a moving subject. The more advanced the AF system, the better it will be at keeping the subject in focus. It’s used mostly in continuous shooting mode for sports and action photography but can also be used for video.

FPS (frames per second)

In stills photography, this is the camera’s maximum continuous shooting speed – the number of frames it can capture per second. In video, this is the number of frames of video per second, typically 30fps, though sometimes 25fps or 24fps.

Continuous shooting

In this mode the camera keeps taking pictures for as long as you hold down the shutter release button. The speed it can take them is the continuous shooting speed, which is quoted in frames per second (fps), and the number the camera can take is determined by the size of the image files, the quality setting (JPEG or RAW) and by the camera’s internal memory buffer capacity.

Burst mode

This is another name for ‘continuous shooting’ mode and it’s the term used by cheaper point-and-shoot cameras – though it’s actually the same thing. In this mode, the camera keeps taking pictures all the time you hold down the shutter button, right up until the time you release the button or the camera’s internal memory buffer fills up and it has to stop to process and save the pictures to the memory card.


This is short-term internal memory used by the camera to store image data captured by the sensor while it’s waiting to be processed and saved to the memory card. It becomes important in the camera’s continuous shooting mode because the camera can capture photos faster than it can save them, so before long this buffer fills up. The larger the buffer, the longer you can keep shooting.

Battery grip

This is an accessory that attaches to the bottom of some DSLRs and mirrorless cameras. It provides a longer battery life for long periods of shooting and it’s popular with sports and action photographers taking lots of shots in continuous shooting mode. Battery grips often have duplicate controls for shooting with the camera in a vertical position, which also makes them ideal for busy portrait and fashion photographers.

Back button focus

Usually the camera will autofocus when you half press the shutter release button, but on more advanced cameras it’s possible to split off focus activation and assign it to a button on the back of the camera. Sports and action photographers generally find this a much more instinctive way to take pictures but it is hard to adapt to if you’re used to the usual method – half-pressing the shutter button.