How to prevent HDR shine/reflection on inside of object?

Hi everyone!

I have objects with a PBR material and HDR reflection textures, for which I would like to prevent HDR shine/reflection on the inside.

Please take a look at the attached image. The object in the screenshot has roughness = 1. But still there is this ‘HDR shine’ on the object. It looks natural on the outside, but not on the inside.

How can I prevent that ‘shine’ without disturbing the lighting? I tried an occlusion texture, but it makes everything dark(er). I just want the ‘shine’ to disappear while keeping the luminosity.

I also tried an emissive texture, but that also changes the lighting, completely removes it.

Any tips or feedback are greatly appreciated!

pinging @sebavan

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The main issue here is that there are no shadows with PBR IBL lighting. your best bet would be to not only lit with IBL and enable shadows so that the interior could be in shadows.

Maybe @PatrickRyan would have some other tricks ?

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Thank you @Deltakosh and @sebavan for your feedback while setting a new time record for support!

As always much appreciated!

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@FernandoConti, the only other things you could do would be to set up a directional light and add a shadow generator in the scene, but you would also need to set up a custom node material so that you could strip out the direct contribution (if you don’t want the lighting to change) so that you can get shadows with no light contribution. You could also generate a shadow map to add shadow to the inside of your mesh.

The problem here is that you will always have specular reflections in PBR, they are just broader as the material gets rougher. Taking them away will change your render, so the easiest way to control them is with shadow or AO. Removing the specular reflections on your material does break the material model a bit, but if you don’t care about that you could set up a custom node material that passes the diffuse contribution for indirect, but not the specular contribution for indirect, and use a mask to isolate that to the faces inside your object.

Not sure if this helps or not, but these are a couple of options you can try.

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Thank you @PatrickRyan! I’ll stick with adding a light, since I need the specular reflections everywhere else. Still, thank you for your help!

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