Factors affecting speedAfter you create your keyframes and motion paths, you may want to make more precise adjustments to the way the spatial coordinates or speed of a moving layer changes through keyframes. You can fine-tune nearly all changes over time using the Speed graph or Velocity graph in the Timeline window. The Speed graph provides complete information about and control of the value and rate of change for all spatial values (such as Position) at any frame in a composition. The Velocity graph provides complete information about and control of the value and rate of change for all nonspatial values (such as Opacity) at any frame in a composition. ![]() A. Speed at the current-time marker B. Minimum and maximum speed (not limits) C. Speed graph D. Speed control The change of value or speed over time is affected by the following factors: Time difference The time difference between keyframes in the Timeline window. The shorter the time interval between keyframes, the more quickly the layer has to change before reaching the next keyframe value. If the interval is longer, the layer changes more slowly, since it must make the change over a longer period of time. Use distance to adjust speed by moving keyframes forward or backward along the timeline. Value difference The difference between the values of adjacent keyframes. A large difference between keyframe values, such as the difference between 75% and 20% opacity, creates a faster rate of change than a smaller difference, such as the difference between 30% and 20% opacity. Use value differences to adjust the rate of change by increasing or decreasing the value of a layer property at a keyframe. ![]() Larger difference (left) creates faster change. Smaller difference (right) creates slower change. Interpolation type The type of interpolation applied for a keyframe. For example, it is difficult to make a value change smoothly through a keyframe when the keyframe is set to Linear interpolation; but at any time, you can switch to Bezier interpolation, which provides a smooth change through a keyframe. If you use Bezier interpolation, you can adjust the rate of change even more precisely using ease handles. For more information, see Fine-tuning speed. |