Vray Lights to render elements / by Mauricio Ricaldi

Control lights is one of the most important thing to do when you light a scene, but also if you separate each light in a different pass or render element is very useful to comp it later and tweak anything without re-rendering all again.

To address this in Vray, we can render each light as separate pass, we need to create an render layer and add the lights and set, geometry, etc.

create a new render layer.

create a new render layer.

As example I have a simple scene that I added five lights.

To have more flexibility in comp I want all the lights in different passes and not all in one RGB like this render:

There is a manual way to do this, assigning each light to a render element and link it, but it takes a lot of time and if you have a bunch of scenes to light, the practical way is to do it with a script.

Phyton script is available at the end of the page :)

Phyton script is available at the end of the page :)

This small script will do the job, you need to place in the render layer (this example city_SET) and add all the lights, run the script, if you need the specular pass there is that option too. 

The script will create for each light a render element:

Now we render and will have all the passes:

From here we can comp in Nuke and add any light effect, color.

RGB render

RGB render

Using the light passes to give some mood and color to the scene .

This way we make candles, torches,  interiors and even characters, and have key lights, fill, rims, etc.. Is a better way to iluminate and has the flexibility to make changes in comp later.

Vray render elements documentation: https://docs.chaosgroup.com/display/VRAY3MAYA/Render+Elements

There is a tutorial for doing this in 3DsMax here.