You probably arrived at this page after pressing pause on Vertigo or Jaws or Raging Bull or Poltergeist or Goodfellas or The Wire . A certain camera trick used in each of them might have broken your brain. While objects in the foreground appear the same size throughout a shot, objects in the background appear to morph in size.
What kind of crazy lens or digital trickery creates this disorienting, hallucinatory effect? Are they using a green screen? A moving platform that carries both the actors and the camera away from the background? Or a special telescoping set that expands and contracts like an accordion?
Nope, It’s All Done In-Camera With a Normal Zoom Lens
That amazing effect is accomplished with a combination of a wide-angle zoom lens, a steady zoom, and a dolly. It is known by many names, including the “dolly zoom,” a “push-pull,” a “reverse-tracking shot,” but is often referred to as “the Vertigo effect.”
That last nickname comes from the first time the trick was used in a mainstream motion picture: Alfred Hitchcock’s Vertigo (1958) used the perspective trick a few times to convey the effects going on in John ‘Scottie’ Ferguson’s (Jimmy Stewart) head. The technique itself is widely credited to Irmin Roberts, the second-unit director of photography for Vertigo. Irmin didn’t even receive an on-screen credit for the film.
To understand the perspective distortion you see in these shots, all you need is a camera with an optical zoom lens, a still-life subject, a nice deep background scene, and, ideally, a grid-pattern overlay for shot composition. First, take a picture of the still-life subject with the lens at its widest-angle setting, and make note of how big the still life looks on the grid-pattern overlay. Next, back up about 5 to 10 steps, zoom in so that the still-life subject has the same size and placement in the frame as the first shot, and take another picture.
Now review those two photos. You’ll notice that the background in the first scene is expansive, with the objects behind your subject appearing smaller and farther away from the camera. In the second photo, those same background objects will look larger and closer to the camera. When the “dolly zoom” is employed in movies, the camera crew is creating a smooth transition between these two extremes. The camera is zooming in or out, and at the same time, it is being physically moved in the opposite direction.
The effect works both ways. You zoom in while moving backward to make the background look like it’s “closing in” on foreground objects—that’s what’s happening in the Goodfellas scene and this clip from La Haine . You zoom out while moving towards the scene to make the background look like it’s telescoping away from the camera—that’s what’s happening in the seminal Vertigo shot, the scene from Jaws, and the expanding-hallway scene in Poltergeist.
DIY Vertigo Effects
You may not have a full camera crew or a bunch of rigs at your disposal, but you can (sort of) pull this effect off in your own videos. Your smartphone isn’t going to cut it because you’re going to need an optical-zoom lens. The lens doesn’t need to have a whopping zoom range, but it has to be able to zoom. For the most dramatic effect, it should have a wide-angle field of view when it’s zoomed all the way out. Your standard DSLR kit lens might work fine.
That said, both manually controlled zoom lenses and powered zoom lenses present their own challenges for a dolly-zoom shot. You’re best off with a manually controlled zoom lens rather than a powered version, as it gives you more precise control over speed and framing. But to eliminate shake and keep the motion smooth, many pros use a lens rig to keep their hands off the barrel. You don’t need one, but you shouldn’t expect Hollywood looks if you don’t use one.
A couple of in-camera settings are key. Autofocus is a bad fit for this shot. You’re going to want to set focus to infinity, or at least deep enough to keep your foreground subjects sharp when you’re farthest from them. You should also use a narrow aperture to keep the depth of field deep.
Obviously, some dolly-like device is going to help keep the motion smooth; you can use a skateboard or a tripod mounted on a cart to keep the physical push-in or pull-back silky. Coordination comes into play when you’re moving and zooming simultaneously, but you want to keep those foreground objects the same size in your viewfinder. That part just takes practice.
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