Animation > Tween
Tween
The term tweening is derived from 'in betweening', the traditional animation term used to describe this process. Tweening significantly reduces the time required to create animation effects such as fading in or fading out, or moving an element across a frame. You can edit tweened frames individually after you create them.

You use the Tween command to automatically add or modify a series of frames between two existing frames-varying the layer properties (position, opacity, or rotation angle) evenly between the new frames to create the appearance of movement. For example, if you want to fade out a layer, set the opacity of the layer in the starting frame to 100%; then set the opacity of the same layer in the ending frame to 0%. When you tween between the two frames, the opacity of the layer is reduced evenly across the new frames.
1. Do one of the following:
 Choose Animation > Tween
 
Click the Tween button
2. Use the following options:
Tween with
Use this option to choose where to add frames:
Next Frame
Adds frames between the selected frame and the following frame. This option is not available when you select the last frame in the Animation palette.
First Frame
Adds frames between the last frame and first frame. This option is available only if you select the last frame in the Animation palette.
Previous Frame
Adds frames between the selected frame and the preceding frame. This option is not available when you select the first frame in the Animation palette.
Last Frame
Adds frames between the first frame and last frame. This option is available only if you select the first frame in the Animation palette.
Frames to Add
Use this option to choose the number of frames to add.
Delay
This option allows you to specify a delay-the time that a frame is displayed-for single frames or for multiple frames in an animation. Delay time is displayed in seconds.
All Layers
Varies all layers in the selected frame or frames.
Selected Layer
Varies only the currently selected layer in the selected frame or frames.
Position (Vector Layers)
Varies the position of the layer’s content in the new frames evenly between the beginning and ending frames.
Angle (Vector Layers)
Varies the angle of the layer’s content in the new frames evenly between the beginning and ending frames.
Opacity
Varies the opacity of the new frames evenly between the beginning and ending frames. Opacity is the opposite of transparency. If something has an opacity value of 100%, that means it’s completely visible. An opacity value of 0% indicates that an object is completely transparent.
Related Information
How Do I > Use the Tween command
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