Taking a better photo - Shutter

Let's talk about shutter speed. I've met a couple of people who either don't know what this is or have a misconception on how this is used.

Shutter speed or S on your dial setting is basically how fast the shutter or the iris on your camera opens and closes. The longer it is open, the more light that comes in. Also, the longer it is open and when there is movement, the sensor captures these movements as well.

The shorter the time the shutter is open, the less light that is captured. And of course, the shorter the time the shutter is open, the less movement is captured or the subject is frozen in time.

Here's an example of long or slow shutter speed. Notice that you see streaks of lights from the headlights and tail lights of the cars.

image from http://www.3jorn.net/blog/wp-content/uploads/2007/07/shutter_long.gif

Here's an example of a fast shutter speed

image from http://farm3.static.flickr.com/2234/2217941883_f40ff0148d.jpg

Here's a side by side comparison

image from http://www.idigitalphoto.com/blog/images/lessons/shutter/shutter-example.jpg

The left side is using slow shutter speed. The right is using a fast shutter speed.

The blurred water you see on the left is because the sensor/film is taking more time to take photos of movement compared to the one on the left where it took a shorter time to capture movement.

An even faster shutter speed will freeze the waterfall even more on the right side. Like if it it set to 1/200 or more.

So depending on what you plan, slow or fast shutter speeds gives you control on how you want your photos to look. They can also control how much light you let in to your lens so it won't be under or over exposed.