Foley is one of the components of a film’s sound design. Foley effects are sounds recorded during post-production to give weight or oomph to subtle sounds that appear on the screen during an actor’s performance and other scenarios.
As I wrote when I talked about the boom microphone, the sound recordist and the production crew are more concerned with capturing dialogue than any other sound during principal photography. Not only does dialogue carry the weight of the story, but you also need an actor to deliver it, which makes the dialogue the undisputed, most important sound element in a narrative film. It can also be the most expensive, if you need Meryl Streep or George Clooney to perform it, which is why on a set you aim your boom mic at the actor’s mouth.
But in the “full canvas of sound,” as foley artist Gary Hecker calls it, other sounds elements are also incorporated in the film. “Little” sounds like footsteps, water running, or an AC humming, need not be recorded on set because they can easily be reproduced during post by foley artists. Here’s how they do it:
The artistry of foley comes from an artist’s resourcefulness to create a sound using unlikely objects. As you see in the video above, foley artist Gary Hecker mimics the sound of the unsheathing of a sword by scraping a metal spatula across a prop sword. In the video, he explains that timing is also a pre-requisite for foley artists. In a single scene, you may have to recreate dozens of sounds before the next breather. To make the process smooth and efficient, it is in everyone’s best interest that foley artists record the effects at the right moment (instead of having to rely on a sound editor to synchronize sound bites every time). This is how crazy it gets:
And here’s another video: