User guide

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Chapter 6, Setting Up Realtime Effects with Adobe Premiere
As you create new keyframes, each keyframe is initialized to the same settings as
the one to the immediate left on the track. This makes it easy for you to define an
interpolation sequence in ascending order (from left to right). If you add a new
keyframe between two interpolated keyframes, however, the new keyframe’s
settings will be calculated according to the adjacent keyframes. For example, if
you add a keyframe between a size setting of 0% and 50%, the size for the new
keyframe will be set to 25%.
¦NoteIf you use the Reverse option for a Matrox effect, the interpolation
sequence is defined from right to left.
Linear and spline interpolation
There are two types of interpolation that you can apply to a keyframe — linear or
spline. Linear interpolation means that the transition between effect settings
occurs in even, linear increments. For example, let’s say you have two linearly
interpolated keyframes 75 frames apart with
Size settings of 0% and 75%,
respectively. When you play back your clip, the size of your clip increases
between these two keyframes at a steady rate of 1% per frame.
If you have three or more interpolated keyframes, linear interpolation might not
give the results you want. Spline interpolation gives you a smoother transition
based on the settings of all keyframes. For example, if you add a third keyframe
(with
Size at 100%) to the example given in the previous paragraph, the
difference between linear and spline interpolation can be illustrated as follows:
Notice how spline interpolation reduces the abruptness in the rate of interpolation
between the keyframes. Spline interpolation is particularly useful for creating
smooth transitions when you move a clip to different locations on the screen.
Creating keyframes outside the clip region
Because spline interpolation is affected by both the number of keyframes and the
distance (frames) between them, you may find it helpful to create keyframes
outside the clip region on the track. For example, you could start your
FRAME
50%
75%
75%
50 100 150 200
100%
50%
50 100 150 200
100%
Linear interpolation Spline interpolation
FRAME