Guest post by Justin McKee
Fair week in Osceola County, which takes place in late July, is a photo-worthy event.
Hundreds of parents go out throughout the week to take photos of their kids showing animals. Most of these parents are sporting slick point-and-shoot cameras, others have their phones handy and a few have invested in a nice DSLR in order to capture the memory of their child at the fair.
The topic of this post is shutter speed, and it is the first of a three-part series. In order to better explain what shutter speed is, let’s take a look at a single day at the fair.
The skies in Evart on this particular day are intermittently cloudy with small spurts of sun popping out between the thick clouds. Children have slowly been coming out to the arena all day to show their animals. Parents have gathered on the bleachers to watch their children show in front of the judge, and many of those parents have brought a camera and are clicking away.
With an outdoor arena, there’s plenty of light for photos. Most of the parents in the crowd are content with the pictures they’ve taken so far. One father in particular, let’s call him “Charlie,” has a daughter, “Annie,” who is showing a pig this year. It’s her third year and she’s having a fantastic day because she just won her first Reserve Champion pig.
The judge comes up to her and shakes her small hand and, with a full grin, she makes her way back into the pig barn. Charlie excitedly gets out of his seat to congratulate her.
Inside the barn and after the hugs resided, Charlie suggests Annie climb in the pen with her animal for a photo.
A problem quickly arises after the first photo is taken, however: The pig won’t sit still. In all the fuss throughout the day Annie’s pig has become restless and, while this modern day Wilbur isn’t necessarily causing a ruckus, each photo Charlie takes has the pig’s movement causing quite a blur.
Therein lies the problem. The pig barn has much less light than the arena outdoors and it has forced Charlie’s camera to use a slower shutter speed.
OK, cute story — what’s shutter speed?
Each camera has a shutter. It’s generally a small mechanism made of aluminum that covers the camera’s sensor. When you click the shutter release button on your camera (the button that takes the photo), you’re telling your camera to lift the shutter out of the sensor’s way and allow light to enter. How quickly that shutter moves out of the way depends on how much light is being cast on your subject.
For cameras set to an automated mode, the camera decides what shutter speed to use by measuring how much light is in front of you. The camera does this as soon as you push the button halfway down, or — for the phone users — as soon as you tap the button that takes the photo. For cameras that allow for manual control, you can choose which shutter speed is best depending on your situation.
Using the barn example, Charlie’s camera saw that there was way less light indoors than out and it readjusted the shutter speed to allow for more light to enter. Think of a camera’s shutter as a flood gate: the longer the gate is open, the more light comes in.
Unfortunately, over longer amounts of time, light changes in the time it takes for the shutter to open and close. How does a camera know how much light to let in though?
Cameras have something called a light meter built into them that measures light using an algorithm. A light meter is what helps cameras set to auto mode properly expose a photo (create a photo that is not too dark or not too bright). Using manual methods, your camera’s light meter can help you decide what settings to use too; more on that in the future.
For many cameras, shutter speed can be as slow as 1/4th of a second (that’s an eternity when taking a photo) and as fast as 1/8,000th of a second. With a slower shutter speed, the light hitting the sensor changes during the course of the shot and can result in a photo with motion blur. Annie’s pig moved during the time that the camera’s shutter was open and that resulted in a blurred motion.
So how does one go about fixing this problem? Well, staying in an automatic mode isn’t going to help any if you plan on staying in the same environment. You could use a flash to add more light to the photo, but not everyone wants their child to have red eyes.
If you’re willing to switch to manual control of the camera, there are a couple things you can do to make sure your shutter speed is fast enough to capture a still subject and still get a photo that’s perfectly exposed.
Hopefully you’ve read your manual as I can’t specify where to find all manual controls on all cameras. It’s different with each brand. For DSLR owners, it’s generally as easy as turning a dial until the “M” is selected. For point-and-shoot/phone wielding folks, getting to manual mode may be a bit trickier as you’ll have to peruse a menu system instead.
Regardless, once you’re in manual mode and have found out which dial or button changes shutter speed, you can from there increase or decrease the speed of your shutter.
Using the numbers mentioned before, a shutter speed of 1/4th of a second is going to be very slow, but it’s also going to bring in a lot of light. A shutter speed of 1/8,000th of a second is going to be VERY fast but there will be less light.
Going back to Charlie, let’s say he knows about shutter speed and how to change the value on his camera. After a second of readjusting his camera, he tries again with a shutter speed of 1/500th of a second. That’ll stop the pig for sure. Much less light is entering the camera and in the amount of time that the shutter opens and closes, the pig’s movement has been essentially halted entirely.
Looking at his camera’s LCD screen, Charlie is met with disappointment yet again … the pig looks as if it’s standing still, but the photo is too dark. Annie and the pig can barely be made out even on the bright screen. Changing the shutter speed helped with one problem, but it also introduced a new one. What went wrong?
I chose the headline for this post carefully. Aside from shutter speed, there are two other functions of a camera that, when balanced together in harmony, create a perfectly exposed photograph. These are called aperture and ISO.
Justin McKee is a small-town photographer with big ideas living in Michigan. In addition to portraits, wedding photography and video, he also enjoys wildlife photography. He always seeks to learn more about his craft.