Learn aboutMovie continuous focus

Short Description

While recording movies, continuous focus means the camera will adjust the focus as you record. This means if you point the camera from one subject to another, the camera will refocus without you having to do anything. Continuous focus makes it dead simple to record movies, without it you have to pay attention to the focus yourself and adjust it as necessary (using either manual focus or one touch autofocus).

These days all the new DSLRs and mirrorless interchangeable-lens cameras record movies, where in the past movies were only possible on point and shoot cameras. However, the first couple of generations of DSLR and mirrorless cameras don't support continuous focusing while recording video, instead they either don't autofocus at all, or they autofocus with the touch of the shutter-release.

Focusing systems

DSLRs have traditionally used phase detection autofocus, whereas point and shoots use contrast measurement. Phase detection requires dedicated focus sensors, and is generally faster and more accurate, and supports subject tracking. Contrast measurement doesn't require dedicated sensors, instead it relies on testing contrast found in the image produced by the sensor.

When recording a movie with a DSLR, the camera's mirror is in the up position, and it is unable to send light to the focus sensors, so DSLRs implement the contrast measurement (also called contrast detection) method of focusing while recording movies. So first generations of DSLRs have had very poor focusing capabilities, but DSLR manufacturers do seem to be working on this problem, though it is unlikely that autofocus capability while recording movies will ever equal still image autofocus unless manufacturers make a breakthrough with contrast detection or design a mechanism to support using phase detection with the mirror up.

DSLRs with continuous focus

These are some of the best SLRs that can adjust the autofocus continuously while recording video.

Mirrorless cameras with continuous focus

These are some of the best mirrorless cameras that can adjust the autofocus continuously while recording video.

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