✨ ReLight Node for ComfyUI

Transform your images with cinematic lighting effects in a single click!

ReLight is a powerful custom node for ComfyUI that adds professional-grade lighting capabilities to your images. Create dramatic shadows, natural window lighting, warm sunset glows, or striking rim effects with precise control over every aspect of your lighting setup.

🌟 Features

Powerful Lighting Control

• Multiple Light Sources - Place up to 3 independent light sources anywhere in your image
• Dynamic Lighting Modes:
  • 🎨 Colored Lights - Add RGB light with controllable intensity
  • 🔄 Color Correction - Apply precise adjustments to brightness, contrast, saturation, temperature, tint and gamma
• Flexible Mask Shapes:
  • 🔵 Circular Falloff - Natural radial lighting with inner/outer radius control
  • ↗️ Gradient - Directional lighting for effects like sunset rays or window light

Advanced 3D Lighting Simulation

• Subject Interaction (when used with mask input):
  • 🔆 Front Lighting - Light illuminates the subject more strongly than background
  • ✨ Rim Lighting - Creates dramatic edge highlighting with background glow
  • 🌐 Standard Lighting - Traditional lighting without subject occlusion

Production-Ready Features

• Ready-to-Use Presets for instant professional results:

  • "Soft Window Light" - Natural diffused lighting
  • "Dramatic Side Light" - Cinematic chiaroscuro effect
  • "Warm Sunset Glow" - Golden hour atmosphere
  • "Cool Blue Moonlight" - Mysterious night-time look
  • "Studio Key Light" - Professional portrait lighting
  • "Rim Light" - Striking edge highlights
  • "Spotlight" - Focused dramatic lighting
  • "Negative Light" - Creative darkening effects

• Visual Debugging - See exactly where your lights are positioned and how they interact

• Fine-Tuning Controls - Perfect your lighting with precision adjustments for blur, strength, and rim amplification

🔧 Installation

Using ComfyUI-Manager (Recommended)

1. Open ComfyUI and navigate to the Manager
2. Search for "ReLight" in the available custom nodes
3. Click Install
4. Restart ComfyUI

Manual Installation

# Navigate to your ComfyUI custom_nodes directory
cd path/to/ComfyUI/custom_nodes

# Clone this repository
git clone https://github.com/yourusername/comfyui_relight

# Install dependencies
pip install -r comfyui_relight/requirements.txt

# Restart ComfyUI

Dependencies

ReLight works best with high-quality foreground masks. We recommend installing:

• ComfyUI Essentials - Provides enhanced mask generation and background removal tools
• Scipy - Required for rim lighting effects (should be installed automatically)

🚀 Quick Start Guide

1. Add the ReLight 💡 node to your workflow (found under category "image/lighting")
2. Connect your source image
3. Connect a foreground mask (white = subject, black = background)
4. Select a preset like "Rim Light (Behind)" or design your own lighting
5. Adjust settings to taste
6. Preview your results in real-time

Sample Workflow

The repository includes a sample workflow file (example workflow.json) that demonstrates:

1. Loading an image
2. Removing the background using ComfyUI Essentials' RemBG nodes
3. Applying the ReLight node with "Warm Sunset Glow" preset in "Behind Subject" mode
4. Viewing the results through both standard preview and debug visualization

Simply load this workflow in ComfyUI to see ReLight in action!

📸 Examples

Dramatic Three-Point RGB Lighting

This example uses three colored lights to create a purposely over the top striking RGB lighting setup:

• Main Settings:

  • 3 light sources
  • "Behind Subject" light direction
  • 2.0 effect strength

• Light 1 (Red):

  • Position: far right (0.99, 0.15)
  • RGB Color: (255, 0, 0)
  • High intensity (2.0)

• Light 2 (Green):

  • Position: left side (0.2, 0.3)
  • RGB Color: (255, 0, 0)
  • Medium intensity (0.7)

• Light 3 (Blue):

  • Position: bottom center (0.3, 0.8)
  • RGB Color: (0, 0, 255)
  • Low intensity (0.2)

This setup creates vibrant color separation while maintaining the "Behind Subject" mode to emphasize the edges of the figure with dramatic rim lighting.

Other Lighting Ideas to Try

Here are some additional lighting scenarios that showcase ReLight's versatility:

Split Lighting Portrait

Create dramatic portrait lighting with a strong contrast between light and shadow:

• Single light source at position (0.05, 0.5)
• Large outer radius (0.8)
• High contrast (25)
• Reduced saturation (-15)
• "In Front of Subject" light direction

Sunset Silhouette

Create a beautiful sunset silhouette effect:

• Light positioned low and centered (0.5, 0.9)
• Warm colors (255, 180, 100) (enable "use colored lights")
• "Behind Subject" light direction
• High rim amplification (3.0)
• Moderate mask blur (60)

Atmospheric Fog Light

Simulate light breaking through fog or mist:

• Light positioned high (0.5, 0.1)
• Cool blue-white color (200, 220, 255) (enable "use colored lights")
• "In Front of Subject" light direction
• High mask blur (100)
• Gradient mode enabled
• Medium intensity (1.5)

Moonlight Through Window

Simulate soft moonlight streaming through a window:

• Light positioned at upper corner (0.8, 0.2)
• Cool blue color (120, 150, 255) (enable "use colored lights")
• Gradient mode enabled
• Low brightness (-10)
• High blue cast (Temperature -30)

💡 Pro Tips

• Layer Multiple Lights - Use several ReLight nodes in sequence for complex lighting setups
• Debug View - Enable show_debug_info to visualize light positions and better understand the effect
• Mask Quality Matters - The better your foreground mask, the more realistic your lighting effects
• Combine with ControlNet - Use ReLight results as input for ControlNet for guided image generation
• Perfect Rim Lighting - For the best rim effects:
  1. Position light behind subject
  2. Use "Behind Subject" light direction
  3. Increase rim_amplification for stronger edges
  4. Keep mask_blur values low (20-40) for crisp edges

📝 Parameter Guide

Core Parameters

Parameter	Description
image	Input image to apply lighting effects
mask	Foreground mask (white=subject, black=background)
preset	Select from pre-configured lighting setups
num_light_sources	How many lights to use (1-3)
use_colored_lights	Toggle between additive color and correction modes
apply_3d_lighting	Enable simulated subject occlusion effects
light_direction	How light interacts with subject ("No Occlusion", "In Front", "Behind")
effect_strength	Master intensity control for all lighting effects
mask_blur	Controls softness of light edges and transitions
rim_amplification	Specifically enhances rim light intensity

Light Positioning

Parameter	Description
light_position_x/y	Normalized (0-1) coordinates of light center
inner_circle_radius	Core area of strongest light effect
outer_circle_radius	Maximum extent of light falloff

For full parameter list, please refer to the detailed section below.

🔍 Troubleshooting

Problem	Solution
No visible effect	Increase effect_strength or light_intensity
Light too strong	Decrease effect_strength or specific intensity/brightness values
Occlusion not working	Ensure apply_3d_lighting is True and mask is connected
Black debug image	Check ComfyUI console for errors
Node fails to load	Ensure scipy is installed
Poor mask quality	Use RemBG from ComfyUI Essentials for better masks
Preset not working as expected	Try toggling use_colored_lights or apply_3d_lighting
Debug image not showing correctly	Enable show_debug_info and check console logs

📚 Detailed Parameters Reference

Core Inputs

• image: Input image to apply lighting effects
• mask: Foreground mask (White=Subject, Black=Background)

Global Behavior

• preset: Pre-configured starting points
• num_light_sources: Use 1, 2, or 3 lights
• preserve_positioning: Keep manual light positions when changing presets
• show_debug_info: Output visualization showing base masks and light positions

Lighting Mode & Occlusion

• use_colored_lights: Use additive colored light instead of color correction
• use_gradient_mode: Use directional gradient masks instead of radial
• apply_3d_lighting: Simulate light occlusion by subject (requires mask)
• light_direction: How light interacts with subject
• remove_background: Composite result using mask

Global Modifiers

• effect_strength: Overall intensity multiplier for lighting
• mask_blur: Blur radius for light mask edges
• rim_amplification: Boost specifically for rim light component

Light Specific Settings (per light)

• Position: light_position_x/_y coordinates
• Shape: inner_circle_radius/outer_circle_radius
• Color (when using colored lights): light_color_r/_g/_b, light_intensity
• Corrections (when using color correction): Brightness, Contrast, Saturation, Temperature, Tint, Gamma

📜 License

MIT License - Feel free to use in personal and commercial projects

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💪 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

🔄 Updates

• v1.0 - Initial Release
  • Added support for multiple light sources
  • Implemented rim lighting and 3D lighting simulation
  • Included 8 professional lighting presets
  • Added debug visualization
  • Improved mask handling and compatibility with ComfyUI Essentials