Onion-skinning

Normally, Flash displays one frame of the animation sequence at a time on the Stage. To help you position and edit a frame-by-frame animation, you can see multiple frames on the Stage at once. The frame under the playhead appears in full color, while surrounding frames are dimmed, making it appear as if each frame were drawn on a sheet of translucent onion-skin paper and the sheets were stacked one on top of another. Dimmed frames cannot be edited.

To simultaneously see several frames of an animation on the Stage:

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 Movie window.

To use onion skinning:

Use the following controls:

To display onion skinned frames as outlines, click Onion Skin Outlines.
To change the position of either onion skin marker, drag its pointer to a new location. (Normally, the onion skin markers move in conjunction with the current frame pointer.)
To enable editing of all frames between onion skin markers, click Edit Multiple Frames. Usually onion skinning lets you edit only the current frame. However, you can display the contents of each frame between the onion skin markers normally, and make each available for editing, regardless of which is the current frame.

Note: Locked layers (those with a Lock icon) aren't displayed when onion skinning is turned on. To avoid a multitude of confusing images, you can lock or hide the layers you don't want onion skinned.

To change the display of onion skin markers:

Choose an option from the Modify Onion Markers context menu:

Always Show Markers displays the onion skin markers in the Timeline header whether or not onion skinning is on.
Anchor Onion Marks locks the onion skin markers to their current position in the Timeline header. Normally, the Onion Skin range is relative to the current frame pointer and the Onion Skin markers. By anchoring the Onion Skin markers, you prevent the Onion Skin markers from moving with the current frame pointer.
Onion 2 displays two frames on either side of the current frame.
Onion 5 displays five frames on either side of the current frame.
Onion All displays all frames on either side of the current frame.