Frame-by-frame animation changes the contents of the Stage in every frame. It is best suited to complex animation in which an image changes in every frame instead of simply moving across the Stage. Frame-by-frame animation increases file size more rapidly than tweened animation. In frame-by-frame animation, Animate stores the values for each complete frame.
To create a frame-by-frame animation, define each frame as a keyframe and create a different image for each frame. Each new keyframe initially contains the same contents as the keyframe preceding it, so you can modify the frames in the animation incrementally.
To add a keyframe whose contents are the same as the first keyframe, click the next frame to the right in the same row. Select Insert > Timeline > Keyframe, or right-click (Windows) or Control‑click (Macintosh) and select Insert Keyframe.
You can convert a classic tween or a motion tween span to frame-by-frame animation. In frame-by-frame animation, each frame contains separate keyframes (not property keyframes) which each contains separate instances of the animated symbol. Frame-by-frame animation does not contain interpolated property values.
Usually, one frame of the animation sequence at a time appears on the Stage. To help draw, position and edit frame-by-frame animations, onion skinning provides reference by displaying contents of the previous and the following frames on the stage. The frame under the playhead appears in full color and apply color and alpha to differentiate between past and future frames.
The previous and the following frames of onion skinning have default color tints. To customize these colors, use the Advance Settings option.
Click and hold the mouse on the Onion Skin button and select Advance Settings.
To modulate the opacity of onion skin frame on either side of the active frame, click and drag the Starting opacity slider.
To decrease the delta of every onion frame by percentage, drag the Decrease by slider.
Click the Onion Skin button . All frames between the Start Onion Skin and End Onion Skin markers (in the Timeline header) are superimposed as one frame in the document window.
Onion skinning color coding helps you distinguish between the past, present, and future frames. Onion skin frames that move away from active frame appear with progressively decreasing transparency.
Color code is also applicable for outline mode.
Locked layers (with a padlock icon) are not displayed when onion skinning is turned on. To avoid a multitude of confusing images, lock or hide the layers you don’t want to be onion skinned.
To check how your onion skinning is coming along, hover the mouse across the entire span on the timeline. Your animation plays in colored outlines giving you a precise preview of the changes.