Tag Archives: photography

OK, those spinning light pictures are kinda cute, but why do you really care about shutter speed if you aren’t trying to capture fire dancers? In short, the shutter speed gives you artistic control of the way your camera captures motion.

One day at work, I heard jets flying very low over my San Francisco office. I happened to have the camera on my desk, so I grabbed it and ran up to the roof to see what was causing the ruckus. I’d completely forgotten that it was Fleet Week in San Francisco, and the Blue Angels were putting on a show for us. I grabbed my longest telephoto lens and started snapping. Since the planes were going by at several hundred miles per hour, I needed a very fast shutter speed to avoid blurriness. This photo was taken at 1/1600 sec, which is pretty speedy.

What if you want to take a picture of your son’s little league game. He’s the pitcher, so of course you want to capture him for posterity. What shutter speed should you use? Well, it depends. Do you want to freeze him in motion just as the ball flies away from him? If so, you should probably use a shutter speed of around 1/500 in order to freeze the motion. Do you want to capture blur from the motion of his arm and see the ball traveling through the air? To achive this result, use something slower, maybe 1/80 or 1/60.

Here’s a neat picture of my drummer friend John. The shutter speed on this was 1/80 sec, which froze almost everything the picture but captured the motion of his drumsticks and his hands. This produces a much more interesting and dynamic shot than if the drumsticks had been completely unblurred– you can almost hear the crash of the cymbal as the fast-moving drumstick comes down on it.

There’s also an interesting remedial component to shutter speed that you should be aware of. Have you ever taken what you thought was a wonderful photo, only to find out later that it was shaky and blurry? It turns out that humans aren’t all that great at holding perfectly still. When we try to take a picture with a slow shutter speed, it doesn’t really matter what our subject is doing. The photographer (that’s us!) wiggles and jiggles around so much that even a picture of a rock will be blurry.

If you’re holding the camera in your hand rather than supporting it on a tripod or some other solid surface, you need to use a fast enough shutter speed that your own motion won’t blur the photo. Some photographers are better at holding still than others, but everybody gets camera shake if their shutter speed is too slow. A general rule of thumb is that your shutter speed should be no slower than the focal length of your lens. For example, if you’re using a 50mm lens, use 1/50 or faster. If you’re using a 200mm lens, use 1/200 or faster. Unless you have nerves of steel, that’s the absolute slowest that you should try to hand-hold a shot. Even you might not be quite that steady; it pays to experiment and figure out how steady your own hands are.

Newer image stabilizing lenses will let you exceed that guideline, but they’re relatively expensive, and they aren’t the cure-all that some people make them out to be.

Thus far, we’ve pretty much just focused on reasons that you might want a fast shutter speed. What about a really slow one? Fireworks are one example. You need a tripod or some other way to stabilize the camera, but fireworks are surprisingly easy to shoot. For this shot, I set the shutter speed to 4 seconds and then did my best to time the shutter so that it opened just before an explosion.

Here’s another great example. Noted nature photographer Joe Decker uses a slow shutter speed to capture the movement of water in this stunning image. Incidentally, Joe has graciously allowed me to use some of his photographs as illustrations on this site. You should check out his work.

Next lesson: How your camera works– the meter

In the last entry I said that there were three basic things that determined exposure: shutter speed, aperture, and ISO. Shutter speed is the first thing we’ll discuss, since it’s easy to understand and its effects are obvious and intuitive.

As I explained in a six-year-olds view of your camera, there’s a sensor at the back of the camera that records light. This sensor is jam-packed with light-sensitive gnomes who do nothing but wait for light to hit them and then record whatever light they see. Most of the time these gnomes are very bored, because there’s a curtain in front of them that blocks out all the light. That curtain is called the shutter.

When you press the button on your camera to take a picture, the shutter opens briefly (or usually briefly, at least) and then closes again. While the shutter is open, light falls on the sensor gnomes and they excitedly write down what they see. In scientific terms we call this taking a picture.

If the shutter is open for a long time, a lot of light hits the sensor gnomes. If it’s only open briefly, the gnomes get correspondingly less light. The amount of time the shutter is open is called, amazingly enough, the shutter speed.

Shutter speed is expressed in fractions of a second, and is most commonly in the range of about 1/30 sec to 1/500 sec, though it can range from many seconds up to the maximum speed of your camera– frequently 1/2000 or 1/4000 of a second. Your camera may identify the shutter speed that way, but more commonly it will only use the lower number. On my Canon, shutter speeds are displayed as 30, 100, 500, etc. Those mean 1/30, 1/100, and 1/500 second respectively. For slower shutter speeds, my Canon uses a slightly different display: 1/4 sec is displayed as 4, but then it goes to 0”3, which means .3 seconds, then 0”4, 0”5, 0”6, 0”8, 1”, etc. 1” is one second, of course. From there it keeps climbing up to 30”, which is 30 seconds.

The neat thing about shutter speed is that it can be used to display motion in your photographs. If you use a really fast shutter speed, you freeze whatever action is happening. Using a slow shutter speed will let you capture motion blur.

In order to illustrate this, I stuck my camera on a tripod and took a series of photos. I used a glow poi (a light-up ball on a string) and spun it in circles while taking a sequence of pictures at different shutter speeds. In the first picture, taken at 1/8 of a second, you can clearly see the motion of the ball as it sweeps around its arc.

At 1/15 of a second, there’s still motion but less of the arc is visible. At 1/125 sec the ball just looks like a blur, and finally at 1/500 sec the ball is completely frozen in its tracks.

That’s how shutter speed works, in a nutshell. Next, we’ll see some real-world examples of why you might want to use a specific shutter speed.

Next lesson: Shutter speed, why you care