What Are PBR Materials?

PBR stands for "physically based rendering." By using PBR materials, you will potentially add a more realistic quality to your renderings. These materials are impressively detailed and seamless. For example, you can distinctively see the texture of a fabric or the grain in the wood!

Rendered Non-PBR Fabric	Rendered PBR Fabric

Here is another example using bubble wrap, which you can download its material files above this article:

Rendered Non-PBR bubble wrap	Rendered PBR Bubble Wrap
Moving a camera around a unrendered Non-PBR bubble wrap	Moving a camera around a unrendered PBR bubble wrap

A PBR material differs from a classic material in that all channels support textures. Also, there are extra channels in PBR compared to classic materials.
These extra channels give the material more information on how to interact with light, therefore can greatly improve how realistic it looks.

CET uses the Disney principled Metallic/Roughness PBR model.
You can visit the Material Properties article to see all other extra channels available in PBR.

To grasp the full potential of PBR materials, make sure you run your renderings in Photo Lab, as quick renders will only be rendered in a downscaled 512x512 pixels.

In Photo Lab, either use the "Realistic" preset in Simple mode, or if you are an advanced user, in Advanced mode, you need to go to Lighting and Shadows and pick either Realistic Light or Image-based Light.

Rendering with any other preset or Lighting & Shadows option will translate the PBR materials of the scene to a non-PBR material.

Converting Materials to PBR Materials

Before converting, there are a lot of considerations before choosing an approach.

• Does the material have PBR additional properties such as metallic reflection, roughness, bump, ambient occlusion, or ability to emit light.
  Materials such as marble, granite, wood, fabric, leather would significantly benefit from the conversion compared to basic colours, and patterns, if they have the appropriate channels.
• Is the material to be used in a rendering where the lighting, angles, movements allow the PBR Material to be expressed in its full potential?
• Are these PBR Material objects significant/clearly seen in the renders?
• Are the Materials being in PBR a large selling point?
• In terms of Extension/disk size, the pixel resolution is a crucial consideration. Are the objects where the materials applied to large enough to justify the high pixel resolution? 
  A good rule of thumb is the textures don't need to be bigger than the number of pixels of the object on average takes up to the final rendering.
• Each PBR channel will add to the RAM usage.
  A fully 2K resolution PBR Material will use 48 MB of RAM.

Depending on your use case, there are different ways which suits your situation.
As such, here some suggested approaches into converting into PBR Materials, starting from the easiest & most recommended, to hardest & least recommended.

1. Reuse CET's PBR material pack.
2. Find similar materials on free websites.
3. Use Material Lab to convert normal materials to PBR materials.
4. Create the remaining materials from scratch using other software (i.e., Substance3D or Scan materials)

Reuse CET's PBR Material Pack

We provide a free CET PBR Material pack Extension containing PBR Materials, where you can reuse/modify the materials inside it to suit your material needs.

If you find one that is almost the ideal material, but want to adjust some properties, you can!

Find Similar Materials on Free Websites

There are a lot of websites who provides a lot of free PBR materials.
Most probably you will find one that is very similar to the material you want to convert.

Support for 3rd Party Materials

The PBR technology used in CET works with most commercial material libraries. Material Lab has support for drag and drop of a zip file containing multiple textures that make up one single PBR material. Material Lab will try to load each texture into the appropriate channel using the names of the files within the zip file (for instance a file name containing "albedo", "base" or "diffuse" will load into the base texture channel).

You can also drag and drop a single texture into the appropriate texture channel and Material Lab will look in the corresponding folder for other texture files and give the user a question if they want to load them into the appropriate texture channels.

Use Material Lab To Convert Normal Materials to PBR Materials

We have a convenient "Convert to PBR" button in Material Lab and Batch Material Converter.
The converted PBR Materials are still saved as *.gm files, and are not backwards compatible prior to 12.0 minor.

and Batch Converter:

Though these seem like an easy approach, it is not recommended for several good reasons.
These conversions are done using some guess work filling in additional properties found in PBR, but not in the old material format.
As such, the resulting conversion could have issues such as:

• Overly sized converted materials, sometimes quadruple the disk size taken from the original material.
• Wrong Metallic/Roughness.
• Wrong Bump map.
• Wrong Occlusion.
• etc.

Therefore, if you really would choose this method, we strongly suggest that you check each converted material manually, especially the disk-size increase, and learning how to properly create 

Create the Remaining Materials From Scratch Using Other Software

While Model Lab does not have a full suite of tools to create PBR Materials, there are other software out there that has!
From proprietary solutions such as Substance 3D from Adobe, to open sourced software such as Material Maker.