Shining emissive light through transparent objects


I am designing a sign that has a stainless steel backing plate and colorless clear acrylic letters. I’m trying to simulate orange and blue LEDs illuminating the letters from behind the stainless steal backer. When I render out with raytracing the letters have a white glow around them rather than orange. How can I make this rendering more realistic?

Thank You,

Design Lab Sign.3dm (1.2 MB)

Here is with a different environment (sun disabled, and using this hdri), and a physically-based material using some subsurface scattering:

And with light intensity boosted some:

And the material is like this:

(I also applied some edge softening to the letters)

Design Lab Sign (modified).3dm (6.9 MB)

So have a go with that and see if it points you in the right direction.


@jdhill Wow! That looks so much better, thank you. How do physically based materials behave differently than standard materials?

Well @nathanletwory could elaborate, but my presumption would be that the standard materials are all internally implemented in terms of the physically-based material – in which case they would just be like “helpers” exposing a limited view for ease & convenience, at the cost of reduced flexibility. For example here, not exposing some subsurface parameters in the standard plastic, to keep things nice & simple.

@jdhill hmm, yeah seems like the physically based materials are more comprehensive at calculating the physics of light, in relation to differing material attributes.

Correct, most of the materials are simplified UIs to the PBR material. The Rhino Custom material is a socalled old-school material. If at all possible don’t use it. The shader graph for it is complex and not as performant as the PBR-based materials.

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