How to Track Moving Objects in Blender

Tracking an object that moves independently of the camera in Blender requires utilizing the Movie Clip Editor's dedicated Object Tracking mode rather than standard camera tracking. This process involves establishing a secondary tracking context within your footage, placing feature markers directly on the moving subject, calculating its unique spatial trajectory, and transferring the motion data onto a 3D Empty using an Object Solver constraint.

Step 1: Prepare the Footage in the Movie Clip Editor

  1. Switch to the VFX > Motion Tracking workspace.
  2. Click Open in the center panel and import your video footage or image sequence.
  3. In the toolbar, click Set Scene Frames to match your timeline length to the clip, followed by Prefetch to load the footage into your computer's RAM for smooth playback.
  4. Set the correct camera sensor width and focal length in the Camera settings panel on the right sidebar if known; otherwise, use default estimates.

Step 2: Create an Object Track

By default, Blender tracks the camera's perspective. You must create a dedicated track context for the independent object:

  1. Locate the Objects panel on the right sidebar (N-panel or tracking settings).
  2. By default, a "Camera" entry is listed. Click the + (Add) button to create a new object entry.
  3. Rename this new entry (e.g., "CarTrack" or "BoxTrack") to keep your scene organized.
  4. Ensure this new object is selected before placing any tracking markers.

Step 3: Place and Track Feature Markers

  1. Scrub through the timeline to find a clear frame where the moving object is fully visible.
  2. Hold Ctrl and Right-Click (or Left-Click, depending on your keymap preferences) on distinct, high-contrast points on the moving object.
  3. Add a minimum of eight continuous markers across the surface of the object throughout the shot. More markers (12–15) provide better stability.
  4. Adjust the pattern and search areas for each marker to account for the object's speed.
  5. In the Track panel, set the Motion Model (e.g., Affine or Perspective for rotating/deforming surfaces, or LocRot for rigid items).
  6. Press the Track Forward button (Ctrl + T) to track the points across the duration of the shot. Manually correct any markers that drift off their target.

Step 4: Solve the Object Motion

  1. Open the Solve panel in the left sidebar.
  2. Define the Keyframe A and Keyframe B ranges to capture significant movement and perspective change of the object.
  3. Check the Keyframe box if you want Blender to determine the best baseline frames automatically.
  4. Click Solve Object Motion.
  5. Inspect the Average Error displayed in the top right of the editor. Aim for an error value below 1.0 px for clean, usable tracks. Remove or adjust inaccurate markers and resolve if the error is too high.

Step 5: Attach the Motion Data to a 3D Object

  1. Switch to the 3D Viewport.
  2. Press Shift + A and add an Empty (such as Plain Axes or Cube) into the scene.
  3. With the Empty selected, go to the Constraints Properties tab on the properties panel.
  4. Add an Object Solver constraint.
  5. In the constraint settings:
    • Set the Movie Clip to your loaded footage.
    • Set the Object field to the custom object track created in Step 2 (e.g., "CarTrack").
    • Set the Camera field to your scene's active Camera.
  6. Click Set Inverse to align the Empty's position correctly relative to the camera view.

The Empty will now follow the exact position, rotation, and scale of the real-world moving object. You can now parent 3D models, visual effects, or masks directly to this Empty by selecting your 3D asset, shift-selecting the Empty, and pressing Ctrl + P > Set Parent to Object.