In my Previous Post, I discussed the three ways cameras capture light, Aperture, Shutter Speed, and Sensitivity. I went into some detail on what each did, and now as promised I’m going to expand on these three. First up, Shutter Speed.
Shutter Speed determines how long light is let onto the recording medium, it is measured in seconds, and more often fractions of a second. On many early SLR like cameras, the shutter speed is set through a dial on the top of the camera, and in some cases, a ring on the actual lens mount. On this selector is several numbers and letters. The two most common letters that will appear on these dials are A and B. “A” will set your camera into Aperture priority mode, where the camera will set the shutter speed for you. “B” stands for bulb mode, which will allow the photographer to hold the shutter open as long as they’d like. On modern SLR cameras the shutter speed is set by using command dials, and selecting the appropriate command, setting ect. Also many cameras now have Shutter Priority mode, which allows the photographer to set the shutter speed and the camera will set the aperture for you. So for today let’s set the camera to Shutter Priority.
By manipulating the shutter speed you can create some dynamic effects, you can capture motion and even freeze time. I mentioned earlier that shutter speed is measured in seconds, and fractions of a second, this is key. We live in a very dynamic world where things can happen in a fraction of a second and then everything has changed, when it comes to cameras they have the ability to freeze that instant moment, if you’re able to have the shutter open for the right length of time.
Most cameras these days can be set to shutter speeds between 30 seconds and 1/5000th of a second (or faster). These are often noted as 30″ and 1/5000″. If you want to freeze a moment in time, you’ll want a faster shutter speed, for the most part anything faster than 1/60″ will be able to freeze motion, anything slower there will be motion blur. In some cases like fast moving cars, sports, and other fast paced action you’ll need even faster shutter speeds, 1/200″ or faster. If you want to create some nice effects and capture the motion, 1/30″ or slower will create some nice effects. But you then have to start worrying about camera shake. Some ways to help with that is to get a lens with some form of stabilization, or use a tripod or monopod to help steady your camera.
So let’s get practical here.
Take for example, you’re down at a river and there’s a small water fall, and it’s bouncing and the droplets are spraying around, and you just want to capture that simple moment with the drops suspended in air. A fast shutter speed will be needed.
(105mm ~ 1/5000″ ~ f/2.5 ~ ISO-320)
As you can see with the above photo, I selected a very fast shutter speed so that you can see the details in the water, it looks frozen, ice-like almost.
Now, let’s flip it around, you have a bunch of people running around, but you actually want to capture this motion in your image for dramatic effect.
(35mm ~ 1/25″ ~ f/2 ~ ISO-1600)
So as you can see, you can drop the shutter speed below 1/60″ and you can see the youth moving around, but still are able to tell that these are people milling about.
For even more dramatic effect, especially at night, are the shots of highways/freeways where you can just see streaks of lights, but can’t actually see the cars, that’s by leaving the shutter open for over a second. Below is an example.
(105mm ~ 30″ ~ f/10 ~ ISO-200)
As you can see, with the shutter open for 30″ the cars have become nothing more than streaks of white and red. Hopefully this has helped you understand how the duration of having the shutter open affects the way motion is captured by your camera. The longer it’s open, the more the motion is captured, whereas a faster speed is more likely the freeze that moment in time.