LogInGal Ravid-Tal shared the process of creating the Extraction project in UE5.4 using Lumen, explaining how the dynamic lighting approach enhances the ice and snow shaders and how detailed motion blur was effectively captured.
Introduction
Hi! I'm Gal Ravid-Tal, a 3D / Unreal Generalist & Compositor currently working at Platige Image. My experience includes movies, TV shows, commercials, and product visualizations.
About Extraction Project
After creating my Dark Ice using Houdini and Arnold, I wanted to test some Ice / Snow shader in Unreal Engine, challenging myself to achieve the best results I can while keeping performance and customizability.
The goals:
- The shader needs to natively work in Unreal Engine using Lumen
- Easy to use
- Non-destructive
- High quality & control over the parameters
Dark Ice project & Arnold material in Houdini:
Shader & Material Workflow
First, I read the documentation of the Subsurface Profile, ensuring I fully understood how it works and how to use it to achieve the desired result.
One important thing to set up in the first place is to enable "Transmission" within the light actor. Otherwise, they will have no Subsurface effect on the asset.
Base Material & Proof of Concept
For the initial phase, I created basic materials using simple Megascans textures, which allowed me to visualize the subsurface quality before diving into more complex setups. I focused on adjusting the subsurface profile parameters to match the asset's scale. Since subsurface scattering is influenced by the global world scale, it's important to tweak these settings, especially for smaller assets, to ensure realistic results. This approach provided a solid foundation for further refinement.
Adding Details
After I was happy with the base result, I added some diffuse texture control, allowing you to adjust any texture making it suitable as snow and an additional a normal layer that added breakup and improved the material look and realism.
Here is an example of using some grass and rock texture as the base but adjusting their Diffuse texture to work as snow:
Lighting Setup
For the lighting setup, I kept things simple, starting with a Skylight actor paired with an HDRI image to provide general ambient lighting.
This combination was surprisingly effective, as the HDRI light was enough to illuminate most of the scene.
Keeping the lighting setup minimal not only made the scene easier to debug but also proved sufficient for achieving the desired effect.
To add more depth and contrast, I introduced a point light with a warm color and applied a noise animation to its intensity.
This dynamic lighting choice created a clear distinction between the cold and warm areas of the scene, enhancing the visual interest and atmosphere.
Rendering Setup
Before rendering my scene in Unreal, I made sure to include a Depth pass, which provides a black-and-white representation of the scene.
This pass is crucial for creating distance-based masks and was particularly useful for integrating 2D elements during the compositing stage.
For global illumination, I chose Lumen, as it delivers fast results with impressive quality. For the actual rendering, I used the UE5.4 Render Graph—a node-based setup that offers significantly more control and flexibility than the traditional Movie Render Queue.
This system allows for breaking the shot into layers, adjusting sample counts for each, and creating collections that can be toggled during rendering.
It's a setup that mirrors the rendering workflows in professional VFX pipelines, where elements like the environment and FX are rendered separately for finer control in compositing.
To ensure maximum clarity and sharpness, I rendered the shot in 4K and increased the temporal sample count to capture more detailed motion blur, achieving a polished and high-quality final output.
Compositing
For the compositing stage, I'm using Nuke. I rebuilt the beauty image by bringing back the different layers and merging them together. Since each layer is independent, I could work on some color corrections for each of them.
I was also exporting the camera from Unreal because I wanted to add some 2D elements, like smoke and an additional blizzard, with more control.
Global Color correction — Masked by Depth pass
Some global color correction, getting some brightness and black level fix along with some background color adjustments thanks to the Depth pass.
Snow & Atmosphere
As mentioned, I wanted to add some 2D stock elements to my scene to improve the overall mood and quality, so I used my camera and Cards in Nuke to place them in 3D space, and by using the depth pass, I masked them out from where I wanted them to not be visible.
Diffusion & Glow
These techniques help to soften the sharpness of the render, giving the snow and fire elements a more organic, atmospheric feel.
The subtle glow enhances the overall visual warmth and smooths out the harsher edges, contributing to a more cinematic and realistic scene.
Final Color Grading & Lens FX
In the final stages of post-production, creative color grading is applied to achieve the desired look for the shot, with an emphasis on enhancing the contrast between "Cold & Warm" tones. This separation helps define the different elements within the frame, contributing to a more cinematic aesthetic.
To soften the ultra-sharp render, lens distortion and subtle chromatic aberration are introduced, adding organic imperfections that enhance the realism of the shot.
A vignette is applied to focus attention, followed by film grain for texture. Finally, a cinematic 2.39:1 aspect ratio is used to complete the look, giving the shot a polished, filmic quality.
I hope this breakdown has been helpful and provides some insight into my workflow. If you have any questions, feel free to reach out to me on ArtStation or LinkedIn.
Big thank you to 80 Level for the opportunity to share my process; it's always a pleasure!