shutter speed

Understanding your camera (part I)

The best way to get out of auto mode and get the most out of your camera is to understand how it works and what goes into making a photo.  Now don't get me wrong, there are many people for whom using auto mode works great and is a perfect solution to their photo taking needs.  However, if you want to get more creative and really start making photos, you'll have to understand exposure.

There are three elements that go into making a "correct" exposure with your camera.  It's best to think of them as a triangle, since they're all connected and each of the three elements affects the other.  You can't change one without affecting the others.  Once you understand the exposure triangle you'll be able to start thinking about getting out of auto mode and exploring the idea of manually adjusting the exposure of your shots.

The three main areas that you can adjust are ISO, aperture and shutter speed.  A lot can be written about each of these areas, so in this post will focus on shutter speed.

Defined most basically, shutter speed is "the amount of time that the shutter is open." In film photography it was the length of time that the film was exposed to the scene you’re photographing and similarly in digital photography shutter speed is the length of time that your image sensor "sees" the scene you’re trying to capture. Shutter speed is measured in seconds, or in most cases fractions of seconds. The bigger the denominator the faster the speed, so 1/1000 is much faster than 1/30.

When you're thinking about what speed to choose, the main thing you need to consider is if there is movement in your scene.  You can choose to either freeze the movement, by choosing a faster shutter speed, or letting the moving object intentionally blur and giving it a sense of movement by using a slower shutter speed.  The actual speeds you should choose will vary depending upon the speed of the subject in your shot and how much you want it to be blurred.

Don't forget, shutter speed is part of the triangle, so as you change shutter speed you’ll need to change one or both of the other elements to compensate for it.  Next time we'll talk about aperture and how that affects the triangle.

Shutter Speed + ISO + Aperture = Your Exposure