Focus Change

Focus moves mid shot to point the audience somewhere new. The camera stays where it is, the frame stays what it was, and attention still travels.

The value is control without a cut. A scene can redirect itself several times inside one take, which keeps the geography intact while the emphasis moves.

The lens travels between focus distances while the shot runs. Nothing else has to change: no reframe, no move, no cut.

The depth stays shallow throughout. If the whole scene is sharp there is nothing to hand over, which is why the entry bans deep focus rather than merely discouraging it.

More than one change can live in a single shot. A multiple rack goes near, far, near, and each stop has to be marked or the throws land in the wrong places.

The two subjects have to sit at genuinely different distances. A metre of separation at portrait range is plenty, and two people side by side at the same distance give the focus nowhere to travel however wide the aperture is.

Use it when a shot has to carry several beats without cutting, and when the relationship between the subjects matters more than seeing each one alone.

Skip it in a short clip. A change needs time at each end to register, so a two second shot rarely has room for one.

Focal shift is the same technique described by its two planes. Focus change is the name used when the purpose is redirecting attention rather than crossing a measured distance.

The distinction is one of emphasis, not of mechanics. Both move the sharp plane inside a running shot, and both need shallow depth to read.

Everything comes back sharp, which leaves the change invisible. Keep the depth shallow, because in deep focus a pull has nothing to reveal.

The other failure is a change with no destination. Say what is sharp at the start, what is sharp at the end, and roughly how long the move takes.