What is Shutter Speed
New to photography? You’ve probably heard the term shutter speed a lot. You probably understand it controls how fast you take a photo but what exactly is shutter speed and why is it called shutter speed?
Simply put, shutter speed is how long the camera sees the world. The camera works a lot like your eyes but instead of walking around with its eyes open and blinking as we do, the camera naturally has its eyes shut and only opens them to take a photo. How long the camera keeps itself open to light (opens its eyes) is shutter speed.
The shutter in shutter speed is a small curtain (usually plastic no days) that protects the digital sensor (or film) from the light entering the lens. When you press the button to take a photo this curtain flips out-of-the-way briefly to let light strike the sensor and record an image. Then the shutter snaps back into place, blocking the light once again. You can’t actually see this happen (the photo is just for illustration) as it is in the body of the camera.
Measuring Shutter Speed
Shutter speed is mostly measured in fractions. When your camera shows a shutter speed of 250 what it means is 1/250 of a second. Shutter speeds of one second or longer are usually noted with a mark such as ‘ on the display to show they are not fractions of a second. The B setting on your camera stands for bulb and means the shutter will stay open as long as you hold down the button. The term bulb comes from the early days of photography when the shutter was moved by squeezing a hollow bulb and puffing air into the mechanism.
Which Shutter Speed to Use
What shutter speed you use will always be dependent on other factors. Things like the light available, what lens you have, the aperture, the subject, and the speed of the subject. However, the fast rule of thumb to avoid fuzzy photos from camera shake is to use a shutter speed at least as fast as the lens is long. In other words, for a 300mm lens, use a shutter speed at least 1/300 of a second. Note that you should avoid going slower than 1/60th of a second without camera support or shake reduction regardless of lens size.
As I said, there are always other factors to consider but there are also some basic starting points for figuring shutter speed when working with action photography if you want to avoid blur. Remember that faster is better when working with movement if you want to freeze the action. Use the highest shutter speed possible for the available light.
Minimum Shutter Speeds for Sports
Action moving towards or away from photographer: 1/500 of a second
Action moving roughly parallel to the photographer: 1/1000 of a second
Minimum Shutter Speeds for Water
Ocean Waves: 1/500 of a second
Splashing Water: 1/1500 of a second