+ Keyframe Interpolation in After Effects CS3 +
Interpolation is used to make more precise changes when you set keyframes or motion paths. In this tutorial we will study interpolation methods in detail.
+ Interpolation +
Interpolation is a process for filling the unknown data between two known values. This process is sometime also referred to as Tweening.
+ Temporal interpolation and the value graph +
Temporal Properties (Such as Opacity) can be controlled precisely using the Value Graph in the Graph Editor. X values are displayed as Red, Y as Green and Z as blue. Download the project and open up the AE Project KeyframeInterpolation.aep. Double click on the 01 – Interpolation footage to open it up. In this comp we have animated position and opacity of the layer. Select the arrow layer and press P for position. Select the Position property and activate Graph Editor. Enable Edit Value Graph option and now from there you can make adjustments to the position values.
+ Spatial Interpolation and Motion Path +
Spatial properties are layer properties that involve movement, such as position, anchor point and effect point properties. When you apply spatial interpolation for a property you change the motion path in the composition panel. The info panel displays the spatial interpolation method. Move current time indicator to middle frame of the position value in comp panel drag arrow downwards in Y direction or enter 400 in the Y value box of the Position Property. Change orientation of the arrow layer to along the path by first selecting the layer and then pressing Ctrl+Alt+O hotkey. Checkout the info panel readout. Spatial interpolation method is indicated as Bezier.
By-default AE applied Bezier interpolation method. If you want to change this default behavior, go to general preferences and enable Default Spatial Interpolation to Linear.
+ Interpolation Types +
No Interpolation
No interpolation is the state where there are no keyframes present. In this state when you set value for a property, layer holds that value for entire length of the layer.
Linear Interpolation
It creates a uniform change between the keyframes. Right click on the middle position keyframe and select Keyframe Interpolation. Choose Spatial Interpolation method to Linear.
Now you can see that not only the shape of the motion path is changed but also arrow takes a abrupt turn when it passes through that keyframe.
Bezier Interpolation
Bezier Interpolation is the most effective and gives you precise control. Unlike Auto-Bezier and Continuous Bezier the two direction handles in Bezier Interpolation work independently of each other. Convert keyframe to Bezier Interpolation and play with the handles.
Auto-Bezier Interpolation
Auto-Bezier also creates a smooth transition between the two keyframes. When you change value of an Auto-Bezier keyframe, directions of the handles also change automatically. If you adjust an auto-Bezier handle manually, you convert it to a continuous Bezier keyframe.
Continuous Bezier Interpolation
Continuous-Bezier interpolation is like auto-Bezier interpolation, however, you set the position of the handles manually.
Hold Interpolation
Hold interpolation is available only as a temporal interpolation method. Use it to change the value of a layer property over time, but without a gradual transition. Use this method when you want layers to appear or disappear suddenly.
Automatically Ease Speed
As you know by now keyframes can be adjusted by manipulating the handles. Easy Ease automates this work for you. After you apply Easy Ease, each keyframe has a speed of 0 with an influence of 33.33% on either side. We have three Ease Methods.
Easy Ease - to ease speed coming both into and out of selected keyframes.
Easy Ease In - to ease speed coming into selected keyframes.
Easy Ease Out - to ease speed coming out of selected keyframes.
Double click on the 03 – Easing comp to open it. Speed easing is applied to middle keyframe on three different layers. As indicated by the text labels.
N – Normal, EE – Easy Ease, EE-I – Easy Ease In, EE-O – Easy Ease Out
Play to composition or render it out to see how arrow speed changes when it approach the middle keyframe.
Double click on the 04 – Ball Animation – Start comp to make it active. In this exercise we will use the interpolation knowledge we just learned. This comp has a ball layer. Select the ball layer and press P to reveal the position property and keyframe it. Since we want to make bouncing ball, our start and end positions will be same for the ball. Press End key to jump to end of the timeline and insert a keyframe of same value. Click on the diamond icon as shown in image below.
Now jump to middle of the timeline and pull the ball downwards.
Preview the animation. We have to put more work in it to make it believable. As ball bounces up, gravity will have effect on it. As ball reaches the top, it should ease in to position before losing all its velocity and start falling towards the earth. Select the last keyframe and easy ease it. Preview the animation and you will see that by applying easy ease in, animation is much more believable. Likewise select the first keyframe and easy ease out it.
Preview the Animation. If you want more hang time at the top, right click on the last keyframe and select keyframe velocity and double the influence to 70%. Turn on the motion blur for the layer and preview the animation.
+Final Output+
+ Download Project +
Dear guest, Only registered members can download projects/footages and Video files.Kindly get registered to download the files. Once you get registered downlaod link will appear here.
+ Other Info +
+ Discuss in Forums