How to Use Onion Skinning in Blender 2D Animation

Onion skinning is a fundamental feature in Blender’s 2D animation workspace (Grease Pencil) that allows animators to see ghosted images of previous and upcoming frames. This article provides a direct, step-by-step guide on how to enable, configure, and customize onion skinning in Blender to streamline your hand-drawn animation workflow.

Step 1: Enable Onion Skinning in the Viewport

By default, onion skinning is active in the 2D Animation template, but you must ensure it is globally enabled for your viewport visualization. 1. Look at the top-right corner of the 3D Viewport. 2. Click the Viewport Overlays dropdown menu (represented by two overlapping circles). 3. Ensure the Onion Skinning checkbox is checked.

Step 2: Enable Onion Skinning for the Grease Pencil Object

Onion skinning is controlled on a per-object basis. If you are working with multiple Grease Pencil objects, you must enable it for the specific object you are drawing on. 1. Select your Grease Pencil object in the Outliner or Viewport. 2. Go to the Properties panel on the right side of the screen. 3. Click on the green squiggle icon to open the Object Data Properties tab. 4. Scroll down to the Onion Skinning panel and check the box to activate the feature.

Step 3: Configure Onion Skinning Settings

Once enabled, you can customize how the ghost frames appear. These settings are located directly under the Onion Skinning panel in the Object Data Properties: * Mode: Choose between Keyframes (shows only actual keyframes) or All Frames (shows every frame, regardless of keyframe status). * Opacity: Adjust the Minimum Opacity slider to control how transparent the ghost frames are. * Frames Before / After: Set the maximum number of preceding (before) and succeeding (after) frames you want to see. * Coloring: Customize the color of past and future frames. By default, previous frames are tinted green/blue and future frames are tinted red/pink, but you can click the color boxes to change them.

Step 4: Toggle Onion Skinning for Individual Layers

You can control onion skinning on a layer-by-layer basis within your Grease Pencil object. 1. Go to the Layers panel (located at the top of the Object Data Properties tab). 2. Next to each layer name (such as Lines, Fills, or Background), locate the small icon menu. 3. Click the Onion Skinning icon (which looks like a stack of three papers) to toggle the effect on or off for that specific layer. This is useful when you want to see onion skins for your rough sketches but not for your final background layers.