Hello, Dolly Zoom

By the accounts I've read, the dolly zoom was first used by Hitchcock in "Vertigo."

You've seen dolly zooms in a lot of movies and TV shows. Sometimes the technique is obvious and sometimes it is not.

In "Vertigo" and "Jaws" the technique is obvious because it causes a dizzy imbalance, mirroring a character's state of mind. Jimmy Stewart is fearful of heights, and Roy Scheider sees his worst nightmare unfold. The dolly zoom puts the audience inside their heads.

The most subtle use of a stereo 3D dolly zoom that I've seen was in "Hugo" when Ben Kingsley took the stage near the end of the move. The dolly zoom brings his head into close up even as it broadens the view of the backdrop curtain with its Man in the Moon motif.

This technique can be accomplished in 2D by laying a dolly track away from the actor and starting at the farthest point with a telephoto framing. As the camera moves forward on the dolly, the telephoto is smoothly zoomed to a wide angle setting. Or the effect can be created in reverse, starting close and wide for the background, and ending far and narrow, with the main subject image size remaining pretty much the same all the way through.

Performing a dolly zoom in 3D introduces another variable, the camera separation, usually called the stereo base. The stereo base could be broad at the telephoto setting and narrow at the wide angle setting, or it could be adjusted any way the movie maker desires in order to achieve an intended effect.

The clip below shows my demonstration rendering of a stereo 3D dolly zoom. The YouTube 3D option is available only on Windows based browsers.


The first thing to notice is that this clip answers the question I raised in the previous post: How much of a rounded object do you see in closeup, compared to the same object seen from a distance?

You see less of a rounded object in closeup than from afar, when the image sizes are held equal. Specifically, you see less, or none at all, of the sides of the object in close up. Imagine viewing the Earth from the Space Station. In close orbit, you see only what is below, up to the horizon, but nothing beyond the horizon. From the moon, you see very nearly an entire hemisphere, the horizon defining the circumference in view.

This is why I rendered the breathing globe in the previous post with telephoto lenses. I wanted to show a whole hemisphere to each eye, and only a very narrow angle of view shot from a distance can do this.

What seems a natural view of the globe is actually quite surreal. You could not show a real globe or the real Earth this way in stereo 3D, unless you positioned the taking cameras extremely far away from the subject and extremely far apart from each other. Even in CG this is complicated.

How easy it is to accept as natural something that is not natural at all!

In the stereo 3D dolly zoom of the head model, notice how the facial features seem to lunge forward, even though the head itself is immobile. I've yet to see anyone use this technique in stereo 3D to conjure a moment of menace.

Hitchcock, the master of menace, would know how to do it.