Use onion skinning
Usually, one frame of the animation sequence at a time appears on the Stage. To help position and edit a frame-by-frame animation, view two or more 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 on top of each other. Dimmed frames cannot be edited.
Simultaneously view 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 Document
window.
Control onion skinning display
-
To display onion skinned frames as outlines, click the Onion Skin Outlines button
. -
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 the Edit Multiple Frames button
. Usually,
onion skinning lets you edit only the current frame. However, you
can display the contents of each frame between the onion skin markers,
and make each available for editing, regardless of which is the
current frame.
Change the display of onion skin
markers
Click the Modify Onion Markers 
button
and select an item:
| Always Show Markers |
Displays the onion skin markers in the Timeline header whether or not onion skinning is on. |
| Anchor Onion |
Locks the onion skin markers to their current position in the Timeline header. Usually, the onion skin range is relative to the current frame pointer and the onion skin markers. Anchoring the onion skin markers prevents them 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. |
