In this tutorial, we will cover how to light and shade a realistic interior scene using a combination of Maya's native lights and Arnold's proprietary lights. This will include how to set up a volumetric light effect with Arnold. Volumetric lighting is the visible effect of light beams caused by light scattering as it hits dust particles in the air. We will also look at how to use light-emitting objects and how they compare to using Arnold's lighting tools. Lastly, we will look at some of Arnold's camera lens options and how to optimize render settings.

 

This tutorial is broken up into the following sections:

Ai Skydome Light
Ai Area Lights
Atmosphere_Volume
Barndoor
Stained Glass Window
Interior Lighting
Emission
Camera Type
Clamp Sample Values
Diffuse Samples

 


Ensure that the 'Visible in Reflections' and 'Visible in 'Refractions' switches are turned on in the Render Stats for the geometry. Sometimes these can be turned off when importing geometry from other applications.

 


Ai Skydome Light

 


Ai Area Lights

Now we will create some lights outside the windows to try to boost light into some of the darker areas of the interior. These lights will represent light coming from the sky.


Atmosphere Volume

We will use a spotlight to create a volumetric lighting effect. 

 


Barndoor



 


Stained Glass Window

Further information about rendering glass surfaces can be found here.



Interior Lighting





Emission

An alternative way to light this area would be to use a mesh to 'light' the scene. This could be achieved using a mesh_light or using emission in the standard_surface shader.

Camera Type


Below you can see the difference between rendering with a perspective lens versus a fisheye lens:

Roll over image

Clamp Sample Values

Now let's look at some ways to improve the quality of renderings. You may notice that we are getting some noise in the reflections of our floor material. This is caused by the bright values from the two lamps in the background. We could increase the specular_samples in the Render Settings. However, this would affect the whole scene and would increase render times. Instead, we can limit the brightness of the pixels in the scene. This will reduce the bright reflections on the floor, thereby reducing the reflected noise on the floor.

 

Diffuse Samples

Below are some examples using various diffuse_samples. By default, Arnold uses two diffuse_samples. However, in the example renders you can see noise in darker areas of the image where there are not enough global illumination diffuse_samples. Increasing the number of diffuse_samples in the scene will help to reduce this particular type of noise. This will improve the quality of the rendering. However, it will also add to your render times, so use this value sparingly. The final rendered image was rendered with 6 Camera (AA) samples and 3 diffuse_samples.


That is the end of this tutorial. If you've followed it all the way through, give yourself a pat on the back, and then try using some of these techniques to light scenes of your own!

 

 

 

 

Modeling credit: Alvaro Luna Bautista and Joel Andersdon.