Achieving the Dolly Zoom Effect Effectively
The dolly zoom effect is an in camera special effect that produces an unsettling look where the subject appears to be stationary with the background changing in size. It can also be executed to make the foreground change in size while the background stays the same. Irmin Roberts, a second unit cameraman working for Paramount Studios, is credited with inventing the technique for producing the effect in the 1950s. The first major motion picture to employ the dolly zoom was "Vertigo," which was released in 1958. Director Alfred Hitchcock used it to demonstrate Scottie Ferguson's fear of heights. Since then, it has been employed in hundreds if not thousands of movies and other media projects. Here's how you can add the dolly zoom into your videos.
What You'll Need
In order to employ this effect, you need to have a dolly and a zoom lens. Dolly track is not needed but is highly recommended because it will help keep a steady camera where the speed of the dolly move can be consistent. If you don't use track, then make sure the dolly is being moved on a flat and level surface. If needed, bring 4' by 8' sheets of plywood.
Performing the Effect
There are two ways to perform the dolly zoom effect. You can either zoom in and dolly out, or you can zoom out and dolly in. What is important is that the subject of the shot remains still while the move is being performed. It is important for the camera operator and the dolly grip to work together and find a speed that keeps the subject at a consistent size during the move.
Why It Works
Seeing a change in perspective without a change in size is unnatural and somewhat unsettling. In real life, we never see this happen so when we see it on the screen, it automatically registers as out of the ordinary to us. Because it is so unnatural, and because it is a special effect that takes time to set up and execute, a director would not include it in his movie unless he was trying to communicate something to the audience.
In "Vertigo," Hitchcock is communicating Ferguson's fear of heights. Spielberg uses the effect in "Jaws" to show Chief Brody's stunned reaction to the shark attack. Scorsese uses it in one of the diner scenes in "Goodfellas" to show how Henry Hill's world is falling apart. Hundreds of other movies have used the effect too.
In fact, it is becoming so common that it is almost cliche. Unless you have a good reason and innovative way to incorporate this effect, you might want to stay away from using it.