The shutter in your camera is a curtain that covers the image sensor and remains closed until the camera fires.

When you press the shutter button, the camera fires, the shutter curtain opens and exposes the sensor to light. The light that passes through the lens and to the camera sensor creatures your photo. This is the shutter mechanism that determines the length of time the sensor is exposed to light. In other words, while aperture controls how much light reaches your sensor, and shutter speed controls how long light reaches your sensor.

What is Shutter Speed?

Shutter speed is the amount of time the shutter is open and light is exposed to the sensor. Shutter speed is measured in a fraction of second and ranging up to seconds. The larger the shutter speed denominator, the faster the shutter opens and closes exposing less light to the camera sensor. When you use lower shutter speed, the shutter is open longer and exposes more light to the image sensor.

Shutter Speed Settings

Each camera has a range of preset shutter speeds available. Common shutter speeds you’re likely to see in most cameras are 1/40, 1/60, 1/125, 1/250, 1/ 500, 1/1000, 1/2000, etc. Shutter speeds on your camera are usually displayed as whole numbers. So a display of 125 is actually 1/125th of a second. Quotation marks are used shutter speeds of one second or more. For example, 2 seconds may be displayed as 2”0 in your camera viewfinder. The Bulb setting leaves the shutter open as long as you like.

High Shutter Speed: Less light, Stop the motion, less camera shake, sharper images.
Low shutter speed: More light, creative blur, more camera shake, a tripod helps here.

Shutter speed and Light Stop

Shutter speed is probably the easiest of the exposure triangle sides to understand. To double the amount of light, we need to double the length of the exposure. For example, moving from a shutter speed of 1⁄60 s to 1⁄30 s will add a stop of light because the shutter will remain open twice as long.

Holding Camera using a Slow Shutter Speed

You need to use a shutter speed that is fast enough to avoid what is known as camera shake. It’s nearly impossible for most people to hold a camera perfectly still. If you’re using a shutter speed slower than 1/60, you’re should probably use a tripod so you don’t blur your photos from movement while you’re holding the camera.

If it’s difficult for you to hold the camera still, no problem. Try using a shutter speed that is one over twice the focal length of your lens. So if you’re using a 50mm lens, use a shutter speed of at least 1/100.

The Basics of Shutter Speed – Video