In this day and age of constantly changing gear and technology, there’s a growing set of vocabulary that we video creators are all expected to learn. With so much jargon being thrown around, it can be easy to forget certain concepts or confuse them with others. A prime example of this is demonstrated by the confusion between frame rates and shutter speeds. Let’s take a minute to clarify.
First, check out this video from --jL, which does an outstanding job explaining the difference between the two concepts:
Now let's recap: Although frame rate and shutter speed are related, they are completely separate concepts.
Frame rate refers to the number of individual frames that comprise each second of video you record, also known as FPS (frames per second.) The most common frame rates in video are 24, 25 and 30 frames per second.
Shutter speed refers to the amount of time that each individual frame is exposed for. In video, the shutter speed you use will almost always be a fraction of a second. The number used in setting a camera’s shutter speed refers to the denominator of that fraction of a second. For example, if you set your camera’s shutter speed to 60, that means that each frame is being exposed for 1/60th of a second.
People often make the mistake of equating frame rate with shutter speed. In other words, some people determine that if they are shooting with a shutter speed of 1/100th of a second, that they are in turn shooting 100 frames per second. This is not the case. Depending on the camera you are using and the frame rate you have selected, you are probably shooting at either 24, 25 or 30 frames per second and exposing each individual frame for 1/100th of a second.
As a rule of thumb, you want the denominator of your shutter speed to be approximately double the number of frames per second that you are recording. In other words, if you are recording at 30 frames per second, you want your shutter speed to be 1/60th of a second.
Even though we generally set the denominator of the shutter speed to be double the number of frames per second, you can achieve some interesting stylistic effects by straying from the norm. Shutter speed can have a very noticeable effect on the look of your video, particularly when it comes to motion. A fast shutter speed such as 1/400th of a second will produce a series of crisp frames that have a choppy look when played back. A slow shutter speed such as 1/30th of a second, on the other hand, will produce a series of slightly blurred frames that have a smoother look when played back.
If you'd like to see for yourself, go find some running water (a park fountain, a faucet, rain, etc.) and film it at different shutter speeds. Or, watch this test video by Paul Hamilton:
The faster shutter speed renders crisp droplets of water and has a frantic mood, while the slower frame rate renders flowing water and a has a relaxed mood. Play around with it! You may find that a higher or lower shutter speed will better suit your style or the mood of your piece.