Help with volumetric lighting - god rays not visible from certain angles

Hey Guys,

I would like to ask you for some help with this lighting setup.

I am designing a heavy mechanical door (rigged and animated). I would like to create this scene where the door is opening and light is seeping through the cracks.

The problem:
I have it all setup with a cube with a principled volume shader and a point light. inside. When I look directly frontal to the door I get the desired volumetric lighting effect. However when I turn away from the door to view it sideways, it doesnt show it anymore.

How do I achieve a sideview shot of light beams slowly seeping through the opening door. What settings should be changed?

I attached a video + blend file

211020_big (2.0 MB)

I think this control may help:

Thank you for the reply. I tried playing with that but i didn’t get it to work. Could you show me?

Could you do what you want using the Sun Beams node in the compositor?

I don’t know where you want the camera… I would say place the camera where you want it and tinker with that setting.

to better see the effect, you can put some noise in your volume, then play with anisotropy and watch it ‘rotate’ the particles.


Your lighting conditions/set up seem to prevent it from being visible. Moving the camera into the volume domain(increasing the domain size or just using a world volume) is also probably a wise thing to do.

I used a spot light here:

Thanks everyone for the help. I think Zender’s advised helped me figure it out. It turns out that you get the desired effect by simply increasing the strength of the lamp to a very high number. However, it only works then for the side camera angle, as going to a front camera view, the image becomes completely ‘blinded’ by strong light. I find it is quite hard to control this effect and it feels a bit counter intuitive to me that you have to increase the lightsource that much.

Don’t worry about lamp strengths as their value is arbitrary and at best a rough approximation. That’s just to say a 10w lamp will never perform like a real life 10w lamp. You can do with less light but it’s directly related to volume density and in turn anisotropy. Scene composition is probably more important(the placement of objects relative to light sources and later the camera/viewing angle(s)). I used a fairly dense value for density btw.

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