180 Degree Shutter Rule

Hi! My name is Vann Tate, and I am the lead cinematographer at Sage Creative. I oversee the filming and editing of all video content. 

When people start making videos, usually they are in pursuit of the elusive “cinematic” look. There are many ways to achieve this in post-production, but I’d like to focus on what we can do in-camera. When shooting, it’s important to keep a close eye on your settings, specifically the shutter speed. In still photography, shutter speed controls how long your shot is exposed, and therefore determines how much motion blur is captured. In video, it performs the same task, but instead of a standalone image, the effect is seen in a series of images. While a high shutter speed in a still photograph creates a sharp image, the same in video can produce choppy movement from frame to frame. It is the cinematographer's job to determine how choppy or blurry they want the video to be. As a rule of thumb, though, most cinematographers abide by the 180 degree shutter rule. 

To understand this rule, we need to go back to the days before digital cameras. When movies were shot on film, the camera’s shutter was a round piece of metal with an opening that spun around to let light in. The larger the opening was, the longer the image was exposed and the more blur was created. After some periods of experimentation, cinematographers decided that the motion blur that most closely resembled that of the human eye was achieved when the shutter was cut in half, creating a 180 degree opening. Sound familiar? This shutter angle became closely associated with the standard film look

The general goal of creating “cinematic” footage is to mimic the film look on digital cameras. So, what better way to do that than to copy the standard film shutter angle? Because the shutter on film cameras was a half-circle, the film got exposed for half the time it spent behind the lens. Therefore, to emulate this look in-camera, your shutter speed should be your frame rate time two. So, if you’re shooting in the cinema-standard frame rate of 23.976, your shutter speed should be as close to 48, or 1/48th of a second, as possible. On standard digital cinema cameras, this task is made even easier by allowing you to choose a shutter angle. 

Now, the point of this post has been to help emulate a standard film look, but, as with all rules, there are exceptions. Just be aware that any variation from 180 degrees will create a noticeable difference in your footage, and it’s best to harness this effect for a specific creative purpose. For example, if you’re shooting an action scene and you want to emphasize the movement with choppy staccato motion, raise the shutter speed. If you’re shooting a disorienting dream-like sequence where actions blend into one-another, you might want to lower it.

So, why does any of this actually matter in the realm of digital marketing? The lesson from this is how to improve the intentionality of your content. The search for the cinematic look can’t be completed overnight, it’s gained and lost and tweaked over years until your visual arsenal grows versatile enough to convey your message with precision. Shutter speed is just one tool you can use to convey a message visually, and hopefully after reading this post you have a better understanding of it.