I have problems selectively rendering light with cycles!

I have a simple scene with 2 layers. On layer 1 I have a ground and light plane. On layer 2 I have a box and another light plane to light the box.

I would like to render this scene so that the light on layer 1 affects only layer 1 and the light on layer 2 affects only layer 2.

How can I do this using Cycles? I’m running Blender 2.67a.

As you can see, the light from layer 2 which is red, casts onto the ground in layer 1. I would like to avoid this. I included the .blend file if someone can please take a look at it.


Test.blend (526 KB)

What do you try to achieve? Maybe there is another way or a workaround …

Provided I am right, you will need to create a light group for layer 2 and this is only possible with internal Blender Render engine. See here, maybe this helps: http://www.blenderartists.org/forum/showthread.php?293154-How-to-Use-Light-Group-in-Blender

I’m trying to make sure, there is not too much color bleeding. For example, if I have a blue ocean plane, no bumps, just a flat plane and I put a white boat in it, it renders with a strong blue tint. Even though that’s true light optics, I want to control this and isolate the colors, so I can have a good clean render for the individual objects. I’m not always trying for photo realism.

In the render layers you can exclude any layer.

  • floor in layer 1
  • cube in layer 2
  • light in layer 3

Create a render layer of layer 1, which excludes layer 3. The light from layer 3 will not light the floor.

Also, a way to limit color bleeding is to limit amount of bounces under Light Paths. Or use blender internal render.

I had the same problem in a render I was creating. I completely forgot about layer exclusion but it works great. Thanks a lot Sago.