2D Relighting in Foundry Nuke: Enhancing Atmospheric & Smoke Effects

Introduction

Relighting footage in VFX digital compositing can be challenging, especially when render passes are unavailable. The 2D Relighting Gizmo in Foundry Nuke compositing provides a powerful way to simulate lighting changes without requiring additional 3D renders.

This tool is particularly useful for illuminating smoke, fog, or atmospheric elements, allowing artists to add realistic light interaction without relying on costly render passes.

In this guide, we’ll explore:

  • How the 2D Relighting Gizmo works under the hood
  • What normals are and why they matter in relighting
  • Best practices for achieving realistic lighting effects in Nuke

What is the 2D Relighting Gizmo?

The 2D Relighting Gizmo allows artists to apply relighting effects directly onto footage by using emboss techniques and normal data, eliminating the need for pre-rendered lighting passes.

 

Key Features of the 2D Relighting Gizmo

No Need for 3D Render Passes – Relight directly in Nuke

Ideal for Smoke & Atmospheric Elements – Adds depth and realism

Adjustable Emboss & Light Direction – Fine-tune highlights and shadows

Works with Normal Data – Achieve physically accurate lighting effects

 

Why is this useful? If you don’t have access to normal passes or relighting AOVs, this tool lets you fake realistic light interaction in film compositing software.

How the 2D Relighting Gizmo Works Under the Hood

Instead of using 3D lighting passes, this tool fakes lighting interactions by manipulating the image’s luminance values with emboss techniques.

 

1. Emboss for Simulated Depth

  • Embossing creates artificial relief, simulating light and shadow interactions.
  • Adjust emboss intensity based on the light source’s incident angle.
  • Use positive or negative embossing depending on the lighting direction.

2. Normal Data for Realistic Shading

  • The tool utilizes normal data (if available) for more accurate shading.
  • Normals help determine surface orientation, affecting how light interacts.
  • Can be combined with color correction nodes to refine relighting effects.

If your footage lacks normal passes, use the Normalize node to generate pseudo-normals from existing depth information.

Understanding Normals in Nuke

What Are Normals?

Normals are vectors that represent the orientation of a surface in 3D space. In VFX compositing workflows, normal data is used to:

Simulate light interactions realistically

Control shading & reflections in relighting setups

Blend 3D and 2D elements seamlessly

 

Using Normals in 2D Relighting

  • Convert footage into normal data using the Normalize node.
  • Apply directional lighting effects based on normal vectors.
  • Adjust light intensity & color grading to match the scene’s mood.

When using 2D relighting in Nuke, always match the light direction to existing shadows for a natural look.

How to Use the 2D Relighting Gizmo in Nuke

 

Step-by-Step Guide

1. Install and Load the Gizmo

  • Download the 2D Relighting Gizmo from Nukepedia or GitHub.
  • Place it in your Nuke Gizmo directory and restart Nuke.

2. Load Your Footage

  • Import your source image or atmospheric element (smoke, fog, etc.).
  • If available, load a normal pass for more precise lighting.

3. Adjust the Emboss Settings

  • Increase or decrease emboss intensity to control light interaction.
  • Set the light direction based on the scene’s illumination.

4. Enable Normal-Based Lighting (Optional)

  • If you have normal data, enable normal-based relighting for improved shading.
  • Fine-tune intensity, contrast, and color correction to match the environment.

5. Render and Compare Results

  • Check before and after renders to refine settings.
  • If needed, blend relighting layers using soft masks.

Use motion blur nodes for a smoother relighting effect on fast-moving elements.

Best Practices for 2D Relighting in Foundry Nuke

1. Match the Light Direction to Existing Shadows

  • If relit shadows don’t match, the effect will look fake.
  • Adjust emboss intensity to match the scene’s primary light source.

 

2. Use Normal Data for Greater Accuracy

  • If your footage contains depth or normal passes, integrate them for realistic shading.
  • Normalize normal maps before applying relighting adjustments.

 

3. Avoid Over-Exaggeration

  • Overusing emboss can make elements look unnatural.
  • Use subtle relighting to enhance realism instead of overpowering the scene.

 

4. Combine with Other Compositing Techniques

  • Mix relighting with color correction, grading, and glow effects for cinematic lighting.
  • Use soft masks to apply relighting to specific areas only.

When using 2D relighting in Nuke, always match the light direction to existing shadows for a natural look.

Common Mistakes When Using the 2D Relighting Gizmo

Using the Wrong Emboss Direction – Always match the light source angle.

Over-Enhancing Highlights – Too much brightness boost can wash out details.

Not Using Soft Masks – If relighting affects unwanted areas, use masks to refine.

Ignoring Normal Data When Available – If a normal pass exists, use it for better results.

Conclusion

The 2D Relighting Gizmo in Foundry Nuke is a powerful tool for adding light interactions to smoke, fog, and atmospheric elements without needing additional 3D render passes.

By understanding how embossing, normal data, and shading work, artists can achieve cinematic relighting effects efficiently.

Looking for more tools? Follow my GitHub for the latest Nuke plugins & scripts!

Frequently Asked Questions (FAQs)

1. Can I use this tool for relighting actors in a scene?

It’s best used for smoke, fog, and atmospheric elements, but it can be applied subtly to relight skin tones and textures.

 

2. Does this require 3D render passes?

No! This gizmo allows relighting without pre-rendered AOVs.

 

3. How do I improve the realism of the relighting effect?

Use normal data if available, and adjust emboss intensity to match the scene’s existing light direction.

 

4. Can I combine this with other lighting effects?

Yes! It works well with glows, volumetric light effects, and color grading for enhanced realism.

“I have not failed. I’ve just found 10,000 ways that won’t work.”
– Thomas Alva Edison.

 

This quote is often attributed to Thomas Alva Edison in reference to his efforts to invent the light bulb. Edison is known for his persistence and determination in the face of failure, and this quote reflects his attitude towards his work. Despite facing numerous challenges and setbacks in his efforts to create a practical and reliable light bulb, Edison never gave up and eventually succeeded in inventing the first commercially successful incandescent light bulb. This quote is often used to encourage people to persevere in the face of challenges and setbacks, and to remind them that failure is an essential part of the learning and innovation process.