What is sliding zoom?

In the push/pull lens, there is a unique way called "Hitchcock zoom", that is, sliding zoom.

sliding zoom is the reverse combination of moving the camera and changing the focal length of the lens, and moving the camera at the same time when changing the focal length of the lens, thus producing a stronger visual impact, even when zooming in a larger range or faster, it can make people feel dizzy.

With the help of slide rail, monopod, stabilizer and other equipment, the camera can be pushed/pulled smoothly, and at the same time, the focal length of the lens can be changed in the opposite direction to the movement of the camera.

Extended information:

Hitchcock zoom is a very cool video shooting technique, which is widely used in various blockbusters to create a tense and suspenseful atmosphere. This technique was first used in the work Vertigo by the thriller master Alfred Hitchcock.

A staircase scene in the movie uses such a special shooting technique, that is, Dolly is matched with Zoom lens, thus creating a visual effect that the distance between the subject and the background is changed, but the size of the subject itself will not change. The expanded or compressed background space creates an oppressive and distorted atmosphere of terror, typical Hitchcock style.

Baidu encyclopedia-zoom

Baidu encyclopedia-Alfred Hitchcock.