Newbie here in blender.

I'm trying to understand how emission node and light probe works together. I have set up a simple scene that has a light source, floor and a circle.

There are things that I need help in understanding:

  1. Whenever I move the plane closer to the light source, the light is not visible anymore on the plane surface. enter image description here

  2. When I do the opposite, moving the plane away from the light source, the light is getting distorted (see image). enter image description here

  3. Lastly, whenever I place an image in front of the light source it does not cast a shadow and the bottom of the circle is also filled with light (I was expecting to have the bottom of the circle darker since it is already beneath). Rather, its having this dark part at the top.

enter image description here

Below are the set up: enter image description here


1 Answer 1


I hope that I'll be as accurate as possible in my explanations:

When you bake the Indirect Lighting, the Irradiance Volume will catch all the light sources of your scene (lights, objects with emission, world) through the little dots that you can see in the cube. Once you've baked, these same dots will give back what they've saved, as if they were small light sources themselves. If they were behind an object and couldn't catch a light, they won't emit anything of course, and therefore will recreate a kind of shadow.

Note that they won't cast shadows themselves. Also, the bake precision will depend on the cube resolution. As for this kind of artefacts, it comes from the combination of these several dot lights, you can avoid that with the Irradiance Smoothing value.

Irradiance Volume came to compensate the light limitations in Eevee (as Eevee doesn't calculate indirect lights, or doesn't take emission into account, etc), it may be useful in some situations but it's probably easier to create new light sources in order to fake indirect lighting, to create shadows for emission objects and so on...


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .