Dolly Zoom

The **Dolly Zoom** (sometimes known as the **Hitchcock Shot**, the **Vertigo Shot,** the **Jaws Effect** or the **Zolly Shot)** is an in-camera effect used to distort perception and create a feeling of unease.

The effect is achieved by zooming a zoom lens to adjust the angle of view (often referred to as field of view, or FOV) while the camera dollies toward or away from the subject in such a way as to keep the subject the same size in the frame throughout. In its classic form, the camera angle is pulled away from a subject while the lens zooms in, or vice versa. Thus, during the zoom, there is a continuous perspective distortion, the most directly noticeable feature being that the background appears to change size relative to the subject.

## History

The effect was first conceived by Irmin Roberts, a Paramount second-unit cameraman, in Alfred Hitchcock's film *Vertigo (1958)*. The shot has since been used in many other films, famously *Jaws (1975)*. Rainer Werner Fassbinder uses the effect twice in one shot in *Chinese Roulette* (1976). Director Joe Dante referred to it as the "Jaws Shot" since the scene in Jaws, when Roy Scheider sees the shark attack of the little boy Alex, is the most famous use of this shot.

## Implementation

The camera focuses on a single point in space (usually the subject). The zoom works to keep the frame crop relatively consistent. And the opposing dolly/zoom techniques nullify the focal point’s visual movement. This keeps the foreground elements roughly the same size throughout the shot. Meanwhile, everything that isn’t the focal point distorts as the perspective continuously changes. This creates the effect we associate with the dolly zoom.

Broadly speaking, dolly zooms look odd as human visual system uses size and perspective cues to determine the relative size of objects. So seeing a perspective change *without* a size change is naturally unsettling.

### Types of Dolly Zoom

How the distortion looks and feels depends on which dolly zoom you use:

If the camera **dollys-*out* and zooms-*in***, the longer focal length creates a heightened magnification and a narrower angle of view, flattening the image. This makes it appear as though the background is *closing in* around the foreground subjects.

If the camera **dollys-*in* and zooms-*out*** the focal length shortens creating a lower magnification and a wider angle of view, curving the image. This gives the appearance of the background *expanding* around the subject.

### Lenses

Dolly zooms can also be a helpful way of seeing the difference between a telephoto lens and a wide-angle lens. In the example from *Jaws (1975*) when the shot begins, the subject is far away from the camera. We can see less of the background because the lens is focused on a smaller portion of what’s in front of it. Then, when the camera pushes forward while zooming out, the focal length changes. This causes the subject's face to stretch unnaturally while more of the background becomes observable. This is, effectively, a shift between a telephoto lens and a wide-angle lens. And the change from one to another makes an emotional point. In this case: a horrific, stomach-turning realization that an enormous shark is chowing down on a child.