What is Clay Render? Learn How to Do it in 3DS Max and Vray
Clay Render is a term used in the 3D Rendering industry. 3D artists perform Clay Renders prior to adding colors and material to their 3D model.
For 3ds Max & V-Ray users
What is Clay Render?
Clay Render is a term used in the 3D Rendering industry. 3D artists perform Clay Renders prior to adding colors and material to their 3D model.
Before we delve into the details of clay rendering, Let’s visit some examples on Behance.
Why do 3D Artists perform a Clay Render?
1. Focus on Shape and Form
The shapes and forms of the geometry are more visible in clay renders than after adding colors and patterns as the color and patterns can create distraction. This is why artists use clay render as a preliminary step to assess if the model looks accurate before proceeding with texturing and material.
2. Finding Errors
Issues like flipped or overlapping faces can cause great problems while rendering the 3D model. A Clay Rendering exposes those errors.
3. Light Balance
If we go straight to rendering the colored version, we might end up adjusting materials where the adjustments were necessary for the lighting and vice versa. So, after establishing a perfect clay rendering, we now know where to make the adjustments.
4. Generate Previews
Clay-render renders much faster. They are ideal for generating previews to get approval from the client. For still image projects, 3D artists send multiple clay renders to clients to choose the final viewing angles so that when applying materials or adding details, the artists can focus only on the chosen viewing angles.
If you are the client on the receiving end of those images, this is the approval stage, not a draft that went wrong. Where it sits in the full sequence is laid out in our 3D rendering process.
A colored version might take multiple times more time than a Clay rendering.
In the case of animations or camera walkthroughs, a clay render performs much better than a viewport grab since a viewport grab does not simulate light.
Clay rendering is one step in a full interior workflow, see how it looks start to finish.
Clay Render vs. Full Photoreal Renders
Understanding the operational divide between neutral matte overrides and full beauty passes helps studios streamline client milestones and prevent wasted rendering cycles.
Clay Render (Neutral Matte Diffuse Override)
Renders significantly faster by overriding complex shaders with a single diffuse gray (128 RGB) material.
Isolates geometric forms and topology errors such as flipped surface normals or overlapping polygons without visual distraction from textures or colors.
Accurately simulates real-world lighting balance, soft shadows, and global illumination bounce unlike flat viewport screen grabs.
Enables clients to lock in compositions and camera viewing angles before artists invest time into high-resolution material creation.
Full Photoreal Render (RGB Beauty Pass)
Requires multiple times more computational time to calculate reflection layers, normal maps, refraction, and complex shaders.
Dark materials throughout the room absorb light, creating an optical illusion of underexposure that can mislead artists into incorrectly increasing light intensity.
Executes final color schedules, physical textures, and material finishes after architectural geometry and scene illumination have been strictly validated.
Serves as the final production milestone delivered for marketing, client approvals, and architectural presentations.
How to make a Clay Render
In this blog, I will show how to create a perfect clay render in 3DS Max and Vray. The example we are using is a living room set we did for a house in NY.
Step 1: Material Setup
First, we will set up the material. It is a simple V-Ray material with a 128 RGB diffuse color.
Step 2: Assigning the Material Override
Then, drag and drop this material to the override material section of the Vray render setup.
Step 3: Excluding Transparent and Semi-Transparent Geometries
Then, make sure to exclude geometries with transparent and semi-transparent materials. So that you can see through where necessary and all lights in the scene simulate properly.
Geometry Exclusion: All Geometries vs. Excluded Curtains
Here is the difference between the two clay renders. The left one is with all geometries included and the right one is with the curtain excluded from the override material.
Balancing Light and RGB Values in Clay Renders
Here is the RGB beauty pass straight from the Vray frame buffer-
So, the rendering might feel a bit dark, and you might have tried to increase the intensity of the light sources. But the clay render below confirms that the lights or properly balanced. The average brightness is already above 128 RGB. The dark materials that are used throughout the scene make us feel that way. So, if we need a brighter feeling in the interior rendering, we must switch to a brighter color schedule.
With clay renderings, we can easily test the scene to make sure that the result we will get in the CGI if we execute these materials in construction.
Client Approval Milestones in the 3D Rendering Process
Clay render is fast and does not take much effort, but it can save you hours and prevent you from creating unnatural results. We run this step on every interior set we produce, which is why clients pick their angles before we spend time on materials. See how that works on our interior rendering services page. You can email me directly at abdullah@7cgi.com.
Have Files to Render?
Ready to verify geometry, balance scene lighting, and produce photorealistic 3D interior or exterior visualizations on time and within budget?
Frequently Asked Questions About Clay Rendering
What is a clay render in 3D rendering?
Clay Render is a term used in the 3D rendering industry where 3D artists perform renders prior to adding colors, patterns, and complex textures to their 3D models. By applying a uniform neutral gray material override across the scene, artists can inspect pure architectural geometry, form, and illumination without distraction.
Why do 3D artists perform clay renders before texturing?
Artists perform clay renders for four critical reasons: (1) focusing on shape and form without color distractions, (2) finding geometry errors like flipped or overlapping faces, (3) balancing scene lighting accurately before applying materials, and (4) generating rapid previews for client viewing angle approvals.
How does clay rendering help diagnose lighting balance?
If an artist renders directly in color, dark materials throughout the scene can make the rendering feel dark, tempting them to incorrectly increase lighting intensity. A clay render with a neutral 128 RGB diffuse material isolates the light simulation, verifying whether illumination is physically balanced (average brightness above 128 RGB) or if a brighter color schedule is required.
Why are clay renders ideal for client approvals?
Clay renders calculate much faster than fully textured scenes. For still image projects, studios send multiple clay renders to clients to choose final viewing angles. This allows artists to concentrate texture detailing and shader refinement only on the approved angles, saving significant turnaround time.
How do you set up a clay render in 3ds Max and V-Ray?
Create a simple V-Ray material with a neutral 128 RGB diffuse color, drag and drop it into the “Override Material” slot of the V-Ray Render Setup dialog, and exclude transparent/semi-transparent geometries (such as window glass, curtains, and light fixtures) so light enters the interior correctly.