Tutorial: What is Shutter Speed?
There is bound to be someone who is going to point out something that isn’t technically accurate with this post, be it with my definitions or diagrams. So, before we start, I would like to state that my sole intention is to simplify, as far as possible, some of the fundamentals of photography. My intention is not to swamp the reader with technicalities but rather to outline the basic principles.
What is Shutter Speed?
The shutter is a mechanism within the camera that controls whether light can reach the sensor/ film. This works much the same way as shutters on a window. Open the shutters and light can flood into a room; close them and the room goes dark.
- Shutter Speed is the length of time that the shutter is open.
- This is measured in seconds or fractions of seconds
- A Fast Shutter Speed means that this mechanism is open for a brief period allowing only a small bit of light to reach the sensor/ film. This results in two things:
- Any movement from your subject will likely appear frozen. This is because the shutter opened and closed faster than your subject was able to move.
- During this time, less light reaches the sensor/ film meaning that the scene will be darker.
- A Slow Shutter Speed means that this mechanism is open for an extended period allowing a greater amount of light to reach the sensor/ film. This results in two things:
- Any movement from you subject will likely appear blurry. This is because the shutter was open for long enough to capture your subject's movement before closing.
- During this time more light was able to reach the sensor/ film meaning that the scene will be brighter.