Mist

Mist adds a layer without taking anything away. The field is still there and the treeline is still there, and a band of moisture lies across the bottom of the frame and separates them.

It also reads as a time of day. Mist belongs to early morning and to the hour after rain, so it dates a shot before anything else in the frame does.

It hangs low, usually between ankle and waist height, and it drifts sideways rather than rolling. The air above stays clear, which is why a misted shot still has a sky and a horizon in it.

Cool light suits it. Mist scatters blue more than it scatters warm light, so a dawn frame reads colder than the same frame an hour later. A low sun behind the mist turns the band bright and hands you a silhouette in front of it.

Drift speed matters on video. Mist moves slowly, and a fast roll turns it into smoke.

Use it for dawn, for a field or a lake, and for a shot that needs a foreground layer between the camera and the subject.

Skip it when you want the background gone. Mist keeps the background, so a scene that needs the world erased calls for fog instead.

Fog fills the frame and takes the distance with it. Mist is a band with clear air above. The test is the sky, because mist leaves you one.

Steam rises in columns from a source. Mist lies flat and drifts sideways. If it is going up, it is steam.

The model gives you fog. Any request for moisture in the air tends to come back thick, so state the height: low, near the ground, with clear air above it.

The second failure is mist that stands still. Ask for a slow lateral drift and give it a direction across the frame.