Lesson 3 – Shutter Speed, Frame Rate

Overview

If a student can understand the basic principles of getting exposure correct through photography, then video should be a pretty easy to make transition. That said, there are some fundamental mechanics of video that require a little bit of extra understanding in order to give a student the full ability to use his or her camera as a tool. Frame rate rarely comes up, but it’s a valuable thing to understand in the raw mechanics of a video, and gives a filmmaker one more “knob” they can turn to get the perfect shot.

Explainer

We don’t tend to think of it this way, but video is really just a slide show of pictures that go quickly enough for our brains not to tell that they’re pictures. Each shot is a frame of the video, an individual picture that makes up the film.

Then, the frame rate is a measure of how many frames there are in each second, the frames per second (shortened as fps). The most common frame rates are between 24 and 30 frames per second, varying between movie films in America (24 fps), England (25 fps), and most television recordings (30 fps). The variants depend on the refresh rate, but then we’re going down an unnecessary rabbit hole, so don’t worry about it. There are exceptions—Peter Jackson’s The Hobbit made headlines for being shown at 48 fps, which gave the movie an almost artificial “pop.”

Here is a useful tool, much like the Camera Sim from Lesson 2, for students to play around with frame rate to see how it works: https://frames-per-second.appspot.com/

There is also a difference between the frame rate a video is filmed at versus the rate it is exported at. When you record a shot with your camera, it records a certain number of frames per second (typically the 24 or 30 fps standards). When you move your footage into your editing software, you can adjust the frame rate of your sequence and export. So if you record something at 60 frames per second, but move it into a 30 frames per second sequence, the editing software will basically not show every other frame.

An editing sequence or export is basically listed in a format that explains the type of recorded footage (a whole ‘nother topic for a whole ‘nother time), its resolution and its shutter speed… so for example:

DSLR 1920p30

1920 is the 1920x1080 resolution, 30 is the frame rate.

A lot of this may seem unnecessary… how are all of these numbers relevant for student videographers? Well first, you want students to have a good understanding of what makes a video a video, breaking it down into its essential elements. From a cinematography standpoint, filming at higher frames per second allows us to get smoother slow motion shots. There’s a whole field of high-speed cinematography that records footage at speeds slower than the human eye can detect. The Slo Mo Guys have made a living raking in that sweet sweet YouTube money doing it, and tend to be a frequent stop of mine on my way down the YouTube spiral into darkness…

Exercise

Now is a good time to have students start filming and experimenting with the exposure triangle of aperture, shutter speed and ISO, as well as playing with the camera’s settings to see if you have frame rate options. Some cameras (such as my favorite Panasonic GH3 and GH4) can record in full HD at 60 frames per second, some require you to turn down your resolution, but it can still provide a fun opportunity.

Aperture and ISO work virtually the same as photography. Shutter speed has a bit of a different role, in that it has an impact on motion blur. The simple rule of higher shutter speed, less motion blur, lower shutter speed, more motion blur typically is all you need to know as a filmmaker, but this video gets into the nitty gritty.