Physical Motion Blur

1. Overview

This addon provides the ability to intuitively control Blender's motion blur settings based on a physical camera's shutter angle (degrees) or shutter speed (seconds). This makes it easy to achieve more realistic and intentional motion blur effects, especially for filmmaking and photorealistic still image creation.

Supports Eevee and Cycles.

2. UI Guide

• Panel Location: Properties > Render > Motion Blur > Camera Shutter Control

• Prerequisite: To use this addon, you must first enable Blender's standard Motion Blur setting.

• Settings Description:

  • Mode: Switches the calculation method between Angle and Speed.
  • Shutter Angle (°): Used in Angle mode. Sets the shutter opening angle (e.g., 180°).
  • Shutter Speed (s): Used in Speed mode. Sets the shutter speed (e.g., 1/50).
  • Frame Rate: Displays and sets the scene's frames per second (FPS).
    • Note: If you change the FPS , click the refresh icon (🔄) to update the calculation.

3. Behavior of Each Mode

Angle Mode

This mode sets the shutter open time as a ratio (%) of a single frame's duration (e.g., 180° = 50%). The final strength of the blur is determined by the distance an object moves between frames.

• For a standard animation (where keyframes are set on specific frames), changing the FPS will not change the visual appearance of the motion blur, as the distance moved per frame remains the same.
• However, if you adjust your keyframes to maintain a constant *real-world speed, a higher FPS* will result in less movement per frame, causing the motion blur to become weaker (shorter).

Speed Mode

This mode sets the shutter open time as an absolute time in seconds (e.g., 1/50 second). The final strength of the blur is determined by the distance an object moves within that specified duration.

• For a standard animation, increasing the FPS makes the object's physical speed faster, resulting in a stronger (longer) motion blur for the same shutter speed.
• However, if you adjust your keyframes to maintain a constant *real-world speed, the length of the motion blur will remain exactly the same* regardless of the FPS, because both the exposure time and the object's speed are constant.