My project at Lightmap this month was to create dirt and dust materials to be applied to a variety of wooden, metal and painted objects. The development of materials is a very challenging subject and by carrying out this project I was able to enhance my material skills further in order to produce the most realistic renders.
To create my dust and dirt material, I decided to use Cinema 4D alongside V-Ray and Octane. I chose this set up because I felt the most confident working with Cinema 4D, and saw this project as an opportunity to solely focus on the materials rather than experimenting with other software I was less confident with.
Dust and Dirt Applied to a Wooden Texture
My first challenge was to apply dust and dirt to a wooden texture and after looking through a number of different references, I came across this really cute, characterful wooden mouse which I decided to use as my reference material.
Now that I had my wooden reference, I started by experimenting with Octane as this renderer had a number of useful material tutorials, which I have included below.
Dirt and Grunge Material
By following the tutorials, I was able to replicate the materials by gradually repeating the texturing creation process until I no longer needed guidance. The ‘screen captures’ below (using free models) demonstrate what I was able to create by replicating, adjusting and implementing the skills shown in the mentioned tutorial. I felt pretty happy using these techniques so I set out to develop the textures for the toy mouse scene, and my ‘render result’ can be seen below:
My next step was to recreate the results of my Octane render within V-ray by using similar methods found in the two tutorials below. I used my knowledge of Octane and adapted this to V-Ray as the process is technically similar, but the methods slightly differ. For example, many of the inputs and nodes share similar names and reactions, meaning I was able to save time by using the same settings and inputs in my materials as I did in Octane. I’ve included ‘screen captures’ of this process in V-Ray (using free models), and then re-created the materials for my scene using V-Ray. The final result is shown below.
Multiple Dirt Shader
I used HDR Light Studio to add lights to reflect off all the surfaces/materials in my scene. By using HDR Light Studio, I was able to maintain the consistency of lighting in both Octane and V-Ray as the software is portable and provides the same lighting set-up (HDRI map) for multiple render engines with precise results. Below is the exported HDRI from HDR Light Studio:
As a direct comparison, my Octane and V-Ray renders are side-by-side below to highlight the differences between both render engines. Each image includes dirt and dust shaders found in both packages, but a noticeable variation can be found on the ears which appear a lot darker in the V-ray render compared to Octane. The Octane render appears more subtle and draws the white scratches to the surface more than the black dirt marks.
After completing the wooden effect on the toy mouse, I set myself the challenge of applying the skills learnt previously to create dust and dirt on painted metal followed by an extra challenge of dust and dirt on a clean object. I felt a retro style radio would provide a really interesting shape and range of materials and came across these images as a reference to guide my model, texture and lighting workflow.
To create the glossy and metal surface material on my vintage radio I started with Octane, a render engine I have used on a number of past projects. My prior experience with Octane meant I able to develop these materials without the need for tutorials.
Before I created the dirt materials on the radio, I developed a few different versions on a separate model, similar to the process I did with the wooden toy. The texture that worked the best for the radio was the one shown below titled ‘Screen Capture.’ I applied the dirt, dust and rust to the radio, and my render is shown below titled ‘Dirt Render.’
I then replicated the material process used in Octane but applied it to V-Ray’s material system. The material process for the clean radio I found to be just as straightforward as I have frequently used V-Ray in my previous projects and feel confident using it.
I decided to experiment with my test scene before applying the dust and dirt to the model, which included testing lots of materials in V-Ray in order to fully understand the process. The ‘Screen Captures’ below highlight this experimentation. Once I had tested the materials, I applied them to the radio which is shown below in the ‘Dirt Render.’
The final four images below capture the results of both my Octane and V-Ray render. Each image features similar dirt, dust and rust shader, but in V-Ray, there is noticeably different colouring. The radio is much brighter and saturated, appearing much softer, whereas Octane has a darker, rustic tone
The dust and dirt material development project allowed me to explore V-Ray and Octane in more depth with the aim of improving my textures and material knowledge. I really enjoyed experimenting with textures and bringing the models to life with materials and lights.
The biggest challenges I came across mainly involved creating realistic dust and dirt in two separate render engines, followed by learning the advanced materials in V-Ray Material. The materials were particularly difficult because V-Ray is still fairly new to me and there were fewer tutorials available to aid my learning.
The two main learning points I will take from this project are the creation of dust, dirt and rust shaders using V-Ray and Octane, followed by enhancing my knowledge and confidence in shader development.