The other materials are not very complex, so I will not introduce them one by one. If you want to learn more about the V-Ray's materials, I advise you to read the content of www.spot3d.com.
Environment and Lighting
In outdoor scenes, I like to set up a basic render environment first, then add some auxiliary lights. In the very beginning, I wanted to create a backlighting scene, but then I got a problem that every backlighting scene has. Look at Fig.42 and you will see a bad dark area on the side of the car.
To avoid this problem, you can add a light in the real world, as shown in Fig.43.
But this is an artificial style. If you want a natural result, you need some other ways. CG is a way to create a hyper-real world; I will introduce this way later.
Now I will introduce you to IBL and HDRI loading - the core of environment setup.
Usually, I used Image-Based Lighting (IBL) to build the main environment. It's very easy to set a V-Ray IBL, which just adds a HDRI to a V-Ray dome light. I set the dome's multiplier to 1.0, which is a standard work habit. I also disabled the Affect Specular option, because I could use standard lights to control the specular manually, and this was faster and easier. Finally, I enabled the Spherical option to create a full spherical environment.
Compared with Vray GI override, IBL is a better choice if you don't have much bounce light, like with an outdoor car scene. It's easier to use and doesn't need many parameters to test, and it doesn't even need GI to lighten the whole scene.
Tips: Using a small and blur HDRI to light up a scene (reflection still needs alLarge HDRI) will reduce render time. But I didn't do this here because I didn't have the time and I was a bit lazy (Fig.44)!