A few weeks back I spoke about one of the advantages of mobile videographer. One of the key features I highlighted was the ability to shoot in slo-motion in 720p on most mobile devices. Let's not forget other DSLR's and video cameras that are able to shoot slo-mo in even higher resolutions.
The biggest question now is how do you go about utilizing the footage you've shot for yourself or a client? There are a variety of techniques we as filmmakers and videographers can use. One of the being speed ramping, which is when you use varying frame rates in a video to bring attention to key moments. Joe Simon and Story & Heart just posted a great tutorial from their Academy of Storytellers that explains the techniques behind speed ramping. Here are some key takeaways.
Let There Be Light
Slo-motion shots are shot at a much higher frame rate than your typical shots. To give this context most films are shot at 24 frames per second (FPS) and videos on the web tend to be 30fps. In general standard slow motion shots are anywhere from 60fps-240fps. In other words if you are shooting at 120fps that's x5 faster than 24fps, which means you'll need x5 more light for your shot.
Three Part Structure
Joe explains that in general speed ramping comes in three parts, " a beginning and ending that are one speed, and a middle that is a much different speed. Often the middle is much slower almost stopping on the key action as it enters the frame." Taking this into consideration, it's easy to think of shot that speed ramps as a story. It has a build up, the climax, and then a resolution. So remember, always utilize they key action as your climax for a more dramatic effect.
Keyframes Are Your Friend
Once you have your footage in your timeline what should you do with it? Joe recommends using keyframes within the timeline to set the in and out point of where you want speed ramping to occur. This not only allows you to visually see where the action happens, but makes it easier to adjust the clip as needed.