We all know the sound that a camera makes. That satisfying click when we press the button and create our photograph. What we’re hearing is the camera’s shutter. That sound is the shutter moving up and down. It moves the same way every time we take a photo, but not always at the same speed. The way our pictures come out depends on that speed. So what is shutter speed? How can we understand it to take intentional and consistent quality pictures each time. Let’s jump in.
Defining Shutter Speed
How does shutter speed work?
Before we jump into the definition, let’s first go over the mechanics of a shutter inside a camera. You’re probably already well-versed in this, so then let it serve as a quick reminder so you can fully understand why shutter speed is so important.
Shutter Speed and Photography
A camera takes a photo by exposing film, (or a digital sensor), to the light. The shutter acts like a barrier; it stays closed to keep the light out when you’re not taking a picture. When you hit the button on the camera to take the picture, the shutter opens and captures the image, and closes when it’s finished.
This interval, this moment in time, is the subject in question. And it applies to both photography and video.
Before we dive into the specifics of how it works in video, here's a general definition.
SHUTTER SPEED DEFINITION
What is shutter speed?
Shutter speed is how long an image is exposed to light, from milliseconds to minutes. If the shutter is left open for a long time, a lot of light is being let in, which could over-expose the image. If you’re in a low-light environment, this could be helpful. If there are moving subjects in your photo, a slow shutter speed could cause motion-blur. If the speed is quick, it’s likely the picture will come out too dark.
Also, fast shutter speed could capture freeze-motion - which eliminates motion from moving subjects and avoids blur.
Shutter speeds are measured in fractions of a second. ½ means "one half of a second," while 1/250 means "one two-hundred-fiftieth of a second." The smaller the number (the higher the denominator), the faster the shutter speed. Conversely, the higher the number, like whole numbers from 1 to 30 seconds, reflect a slow shutter speed.
FAST SHUTTER SPEED VS SLOW SHUTTER SPEED
- If the room is dark, use a slow shutter speed to let the light in.
- If the room is bright, use a faster shutter speed .
- If you’re taking a photo of a moving target, a fast speed might be best.
- If you’re trying to capture the movement of a subject, a slower speed is best.
Take a look at the video below. Notice what happens to images as you increase the speed of the shutter.
Most mirrorless and DSLR cameras have a large range of shutter speeds. It usually depends on the quality of the camera. Most DSLRs can go from 1/4000th to 30 seconds. While some can climb to 1/8000th, depending on the model. This is just one of the differences between DSLRs and mirrorless cameras.
What About Shutter Speed for Video?
There's something called the 180° Shutter Rule. The rule explains the relationship between shutter speed and frame rate. Frame rate (frames per second or FPS) is the frequency (rate) at which consecutive images called frames appear on a display. Let's define the rule and see how shutter speed and frame rate work together.
180° Shutter Rule Definition
what is the 180-degree shutter rule?
The 180-degree rule states that your shutter speed should be set to double your frame rate. This is a film industry standard and is sometimes referred to as "cinematic shutter speeds."
*Most DSLR’s have the option to shoot at 1/50th but not 1/48th, so if you're shooting at 24 frames per second, it's best to set the shutter speed to 1/50th.
The shutter angle is the camera’s shutter speed relative to the frame rate.
Adjusting the shutter angle is a way to "break" the 180° rule. Remember, this is not to be confused with the 180° rule related to staging your scene.
If you have a wide shutter angle, anywhere from 270° to 360°, your shot will appear shaky, and will have greater motion blur. This could be useful for creative purposes depending on the narrative or story you're trying to tell.
Of course, the opposite is true — shooting with a narrower shutter angle, the less motion blur from frame to frame.
To recap, a higher shutter speed will give your footage a slightly unnatural look, and sometimes that's what you want. To approximate human vision, keep your shutter speed at 1/50th of a second.
WHAT ELSE TO CONSIDER
Adjusting your shutter speed
Of course there are other things to consider when taking a picture besides shutter speed. This article won’t go in depth into these other components, but they are just as critical.
This refers to the opening of the lens. When you hit the shutter release button to take the picture, a hole opens to capture the image. The aperture is the size of that hole. The larger, the more light gets in, and the smaller, the less light. They’re measured in ‘f-stops.’ Moving from one f-stop to another either doubles the size or halves it. **As the number increases, the size of the hole actually gets smaller.
You’ll see a number like f/2.8 which indicates a bigger aperture whereas something like a f/22 would be a very small aperture.
This measures the sensitivity of the camera's digital sensor to light, (or the film’s sensitivity, if using a traditional camera). The higher the number indicates the sensor is more sensitive to light — 100, 200, 400, 800, etc.
100 is considered standard. Higher numbers are best for darker situations. But keep in mind, higher ISO could cause grainy images. Using all three ISO, aperture, and shutter speed help to balance this.
A higher ISO would also work well if you are capturing a sporting event that’s in lower light. If your subject is moving fast, you can’t have a slow shutter speed or the image will be blurry. If you want a sharp, well-lit image, you could raise the ISO for light, and keep a fast shutter speed to freeze the image.
Watch the video below, of all three components — shutter speed, aperture, and ISO, working together. Shutter speed is but one point on something called the exposure triangle.
We briefly mentioned frame rates regarding shutter speed for videography. Our next post dives into how to manage and control your frame rates for the best shot possible.
What is aperture?
This article mentioned aperture and how it works with shutter speed. But if you want more control over your photos and videos, you'll need to go a bit deeper. Knowing all three points on the exposure triangle is critical to fully grasp your capabilities with the camera.