In all DSLR cameras there is a piece of plastic in the lens called the shutter. When you press down the button on your camera to take a picture this opens the shutter, and it records the light in front of the camera. The time it takes to let in the light is known as the shutter speed, or exposure time. On your DSLR there are many different shutter speeds you can choose from, and many different uses for each.
Longer exposure = More light, Shorter exposure = Less light
Here are a couple different shutter speeds you can use:
B or Bulb, 30", 1/20, 1/60, 1/125, 1/2500, 1/4000
This list of shutter speeds is from slowest to fastest. B or Bulb is a manual shutter which lets you control how long it is open and how much light is absorbed. The shutter is open for however long you hold the button. 30" is 30 seconds. Sometimes you will see 2"5, which is 2 and 1/2 seconds, so it's not too difficult to understand. 1/20 is one twentieth of a second, so on and so forth. Do note, to take a picture with a long exposure time you will need to use a tripod, or else it will be a very blurry picture. I would recommend using a tripod up until 1/60. This will ensure a nice clear picture.
How to choose a shutter speed
When choosing a shutter speed you need to decide what you are taking a picture of. If it will be dark you will need a longer exposure, and probably a tripod. If it is going to be light outside you will need a faster shutter speed. It also depends on what your subject is doing. If you are going to a soccer game and would like to get good action shots, a faster shutter speed is the way to go. Longer exposures can be used for night snots and light painting (Tutorial on this later).
You will have to read in your camera's manual to see how to set your shutter speed, since not every camera is the same. I have a canon EOS T3i and there is a dial located in front of the shutter button, and that is what I use to change the speed.
Examples of what you can do with different shutter speeds:
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| Fast Shutter Speed Example. Good for action shots. |
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| Long exposure using Sparklers. Really cool Effect |
