The shutter inside your camera blocks the light that is coming through the lens from reaching the camera’s sensor. Think of it like mini-blinds on a window that won’t allow any light through from outside. You are the “sensor” inside the house. When you push the button to take a picture, the shutter opens and allows the light to pass through the lens and onto the sensor. The time it takes for the shutter to open and close is called the shutter speed. Shutter speeds can vary from hours to a fraction of a second. In fact, most photography is shot between 1/30th and 1/250th of a second.
The faster the shutter opens and closes, the more ability you have to stop, or freeze action. A very short math review: 1/250th of a second is faster than 1/30th.
If movement is occurring in your shot, and a slower shutter speed is used, the movement will be recorded as blur. There is also a point, usually anything slower than 1/30th of a second, when the shutter speed is too slow to handhold the camera still enough to get a clear picture, so the camera needs to be put on a tripod. Using a tripod allows you to shoot with slow shutter speeds because you have removed yourself, and any movement, from the camera when it’s taking the picture.
In the next installment we’ll look at a few examples of using different shutter speeds in real life situations.