MAKING VOLUME LIGHT
In this section we will explain how to make volume light in Octane using 3 different methods. Volume is a fairly wide issue; so we will not go into the details of using the volume in these examples. You can look at "Volumetrics" for this. There are a few ways to create a volume light in Octane. First look at Realistic usage.
Creating spotlight volume by using octane volume object (realistic)
1- In the "Making Spotlight" section, reopen the spotlight scene we provided. This time we will define a "Volume" to the spotlight. Now that you know how to make Spotlight in general, you can also load your own scene or spotlight setup for this example. First go to the "Objects" menu in Live Viewer and select "Fog Volume". Once you've created Fog, set the dimensions of this volume object from the viewport so that it covers the spotlight. You can enlarge the volume object with the scale tool. Be careful because it will scale uniformly because of the nature of the volume object (usually consuming too much GPU power and Vram). Perform setup as you see in the picture below.
2- You no longer need to do any action in the viewport from this point. Now the whole action will be in the Medium setting of the Volume object. So go to the medium tab and change the settings as you see in the picture below. Do not worry, we will describe volume and medium options in more detail in the "Volumetrics" section.
3-Before running Live Viewer, go to the Octane settings and select Path Tracing as the render kernel. Apply the options you see below.
4- If you've done everything right, you'll see something like the following render (except cosmetic factors). As you can see in the picture, spotlight interacts directly with the volume object, giving a realistic result. By putting the "Fog Volume" in the medium, you can actually imagine that you are theoretically filling up the space with very small particles. Just as in the real world, photons interact with these particles and scatter (or absorb) to give us a foggy or hazy appearance.
1- This time we will create the same scene and spotlight setup using the environment. To do this, first create a "Texture Environment" from the Live Viewer and go to the main tab and set the options as you see in the picture below.
2- Now go to the medium tab and make the settings you see in the picture below.
3- You can set the Render kernel as the previous example. Depending on the scene, some settings may need to be changed. It is important to choose the kernel method as Path Tracing in every scene you use Medium. If you've done everything right, you'll see something like the following render (except cosmetic factors). As you can see in the picture, spotlight interacts directly with the environment volume, giving a realistic result. If necessary, you can increase or decrease the power of the light.
Creating spotlight volume (non-realistic)
1- In the "Making Spotlight" section, open the spotlight scene we link to. This time we will give a volume effect to a cone object, not to the environment. First create a Cone object and position it where you want in your scene. Then right-click on this cone object from the object manager and select "octane object tag" by selecting c4d octane tags from the drop down menu. Set the options as follows.
2- Now create the Octane Specular material and open the Material Attribute window with a double click. In this window, close all channels except Index, Medium, Fake shadows, Common and Editor. Go to Fake shadows and activate it. Make Index 1. Now go to the Medium settings and change them as shown below. After finishing the Medium settings, assign the material to the cone object.
3- Run LV. If you've done everything right, you'll see something like the following render (except cosmetic factors). As you can see in the picture, the volume medium we assign to the cone object is quite far from the previous realistic samples; especially the edge of the cone object is very sharp. But since this method is practical, you can use this setup according to your purpose.