Choreography: Shooting Slow Motion

When teaching choreography dances, sometimes it may be best to record the dance either using a slow motion camera or by simply slowing down the entire sequence. If a slow motion camera, however, is out of the picture, then Adobe After Effects time-stretching effect may be a better choice.

Step 1: Using a Slow Motion Camera

Slow motion cameras are able to capture a high number of frames per second. While these additional frames were only captured in a few seconds, the sequence will play back slower because there are so many of them.

For example, the Phantom digital high speed video cameras can capture upwards of a 1,000 frames per second. This means that it is capturing 1,000 frames in the course of one second. Yet, while this was filmed within that one second, it will not play back that way. All these frames need to play out on the screen. So, those 1,000 frames could play out for nearly 30 to 45 seconds. This will create the slow motion effect.

Most people, however, will be unable to afford these high speed video cameras because of cost. These video cameras cost several thousands of dollars. So, unless the filmmaker is a professional, then it just does not make sense to spend all this money just to create slow motion effects.

Step 2: Time Stretch in After Effects

Adobe After Effects has a way to speed up or slow down a single layer. This effect is known as time-stretching. Basically, this will change how long the sound and clips will run over a specified amount of time. Try to only slow down the sequence as little as possible. If the new time frame is only slightly different than the source frame rate, then the sequence will not be as distorted.

Step 3: Time-stretching from a Specific Time

If choreographer only wants to slow down a small section of video, this can be done by using the time-stretch from a specific time option. To change the frame rate from a specific time, go into the Composition panel and choose the layer.

Next, go to Layer and then Time. Select Time Stretch in the Time menu. Either add a Stretch Factor or just the new time over which the layer should be played. Now, select a Hold in Place option and then select OK.

Step 4: Time-stretching Over a Certain Time Period

If a choreographer wants to slow down a video to a certain length, this can be done by stretching out the video over a specific time period. To do this, go into the Timeline panel and drag the current-time indicator to the frame where the slow motion effect will begin and/or end.

Next, bring up the In and Out columns, which can be found on the Timeline panel menu. To lengthen the In point to the current time indicator, hold down control and click on the In time in the In column. To lengthen the Out point, hold down control and click the Out time in the Out column.