User Guide

CHAPTER 6
228
Fine-tuning Animation
When remapping time in the Timeline window, use the values represented in the Time
Remap graph to determine and control which frame of the movie plays at which point in
time:
Time Remap This value indicates which frame plays at the current time. As you drag a
Value graph marker up or down, this value changes accordingly. You can click this value
and type a new one. The Time Remap value also appears in the Layer window next to the
Out point value.
Value: Time Remap The top value represents the last (highest) frame in the layer, and the
bottom value represents the first (lowest) frame.
Velocity: Time Remap The top value indicates the layer’s fastest speed. The bottom value
is always a negative of the top value. The middle value indicates how fast the video is
playing at the current time. Normal speed is 100%, slow-motion is less than 100%, and
fast-motion is greater than 100%.
When you turn on Enable Time Remapping, After Effects adds a Time Remap keyframe
at the start and end points of the layer in the Timeline window. By setting additional
remap keyframes, you can create complex motion effects. Every time you add a Time
Remap keyframe, a Value graph marker appears on the graph directly below the keyframe.
As you move this marker up or down, the Time Remap value changes to the frame of the
video set to play at the current time. After Effects then interpolates intermediate frames
and plays the footage forward or backward from that point.
The speed at which remapped video plays depends on the number of frames you are
remapping and the amount of time allocated in the timeline for the changes. For example,
if you freeze a frame for one second and do not increase the duration of the layer by one
second, the footage following the freeze frame must play faster than normal to play all
frames in the limited time remaining.
The original duration of the source footage may no longer be valid when remapping time,
because parts of the layer no longer play at the original rate. If necessary, set the new
duration of the layer before you remap time. See “Understanding trimming” on page 139.
If you remap time and the resulting frame rate is significantly different from the original,
the quality of motion within the layer may suffer. Apply frame blending to improve slow-
or fast-motion effects; see “Using frame blending” on page 150.
UG.book Page 228 Wednesday, February 21, 2001 12:05 PM