Mastering Motion Brush in Seedance 2.0: The Ultimate Guide

What is the Motion Brush?

The Motion Brush is a way to apply motion selectively. Instead of asking the whole scene to move, you paint a mask over the area you want animated.

Want the clouds to move but the mountain to stay still? Want a character's eyes to blink but their head to remain frozen? This is the tool for you.

If you haven’t used image-to-video yet, start here first: Image-to-video workflow.

How to Access It

1. Upload an image to the Image-to-Video tab.
2. Click the small "paintbrush" icon overlaid on your image thumbnail.
3. This opens the Motion Editor.

The tools: Brush vs. Eraser

• Brush (Green): Adds motion to the painted area.
• Eraser: Removes the mask.
• Size Slider: Adjusts the brush size for fine details (like eyes) or broad strokes (like sky).

Rule of thumb: Start with a bigger brush than you think, then refine edges with the eraser. Jagged masks often cause jitter.

The Secret Settings: X, Y, and Z Axis

Once you've painted an area (e.g., a car), you tell it how to move using three sliders:

Horizontal (X-Axis)

• Left (-10) to Right (+10).
• Use for: Cars driving across the screen, characters walking past.

Vertical (Y-Axis)

• Up (-10) to Down (+10).
• Use for: Elevators, falling rain, rising smoke.

Proximity (Z-Axis)

• Away (-10) to Toward (+10).
• Use for: Objects coming closer to the camera or receding. Crucial for 3D depth.

Tip: Keep values small at first (±1 to ±3). Big values can cause warping, especially on faces/hands.

Practical Example: Animating a Waterfall

Let's say you have a static photo of a beautiful waterfall.

1. Paint over just the water (avoiding the rocks).
2. Set Vertical (Y) to +3 (Down).
3. Set Horizontal (X) to 0.
4. Set Ambient Noise to 2 (adds random turbulence).

Result: The water flows naturally downward, while the rocks remain perfectly sharp and rock-solid. Without the brush, the whole image might have warped or drifted.

Common mistakes (and quick fixes)

• Mistake: brushing over the face/hands. Fix: keep faces/hands unmasked; animate background elements instead.
• Mistake: too much motion everywhere. Fix: lower motion strength and reduce axis values.
• Mistake: hard mask edges that shimmer. Fix: re-do the mask with smoother edges and smaller values.

If you’re fighting face/hand distortion, this guide helps: Fixing faces & hands in Seedance 2.0.

Pro Tip: Dual-Brushing

Did you know you can use multiple brushes with different settings?

• Brush 1 (Blue): Paint the sky. Set specific motion (clouds moving left).
• Brush 2 (Red): Paint the grass. Set specific motion (swaying right).

This creates complex, layered movement that looks incredibly expensive and professional.

A reliable mini-workflow

1. Start with a strong still image (composition locked).
2. Brush environment first (sky, water, flags, hair only if it’s not crossing the face).
3. Use small axis values.
4. Generate multiple variations and pick the one with stable identity.