Exclude an object from Arnold sky lighting

[piogil]

I have an indoor scene lit with Arnold Sky and Light Portal among others.
I want to exclude an object (dog) from the sky lighting. In the project tab I have excluded it but it continues to receive lighting (little but I need it to not receive any)
As you can see in the image, all lights are inactive except sky, and the dog is excluded in the projects tab.
In the IPR window you can see that he is still receiving light.
Any ideas why this is happening and how to fix it?

Thanks and greetings

[peter_horvath]

Is it indirect lighting? You can check the direct and indirect AOVs.

[piogil]

Hi Peter,

Thanks for your interest.
It's actually indirect light.
In the direct light render it appears completely black

[peter_horvath]

I don't think it's doable, light linking works only for direct lighting. @lee_griggs @Stephen.Blair can you think of any workaround?

[lee_griggs]

You don't want indirect_diffuse on the dog? You could disable it in the standard_surface (Advanced) shader.

[piogil]

I have tried this solution and it works with the standard material, the problem is that the dog is covered in hair. I have tried to reduce the indirect diffuse to zero on the standard hair but it continues to receive indirect light from the sky.
This lighting generates an undesirable effect with many artifacts on the hair render that do not disappear no matter how much I increase the samples.
If I remove the light from the sky the hair looks perfect, but the rest of the scene is affected. This is why I need to avoid the light from the sky on the dog.

[lee_griggs]

Maybe a rayswitch shader would help with this?

[piogil]

I will try this possibility.

Thanks

[piogil · Accepted solution]

It hasn't worked.

I have not been able to eliminate the indirect light from the sky
I had to change the lighting of the scene without the sky.
Thanks for the contributions

[lee_griggs]

Did you try the skydome_light.indirect?

[piogil]

Yes, but the result affects the entire scene, not just the dog.

[peter.fagerberg]

Maybe try dual renders; one where diffuse light hits the dog and one with diffuse turned off. If you use an object mask for the dog you just add it on top in post? For sure, it's a bit cumbersome but maybe the final result is worth it?

Best regards, ///Peter

[piogil]

Thank you for your suggestion Peter.
The problem is that it is an animated scene with about 300 frames.
It will take me less time to redo the lighting without the sky.

Best regards

[lee_griggs]

I would bite the bullet with AOVs. This is what they were designed for.

Why don't you want indirect lighting on the dog anyway?

[piogil]

For some reason the indirect light from the sky causes strange artifacts in the render of the dog's hair that I have not been able to eliminate even though I have tried with high AA samples.

I don't really understand how AOVs work. I will study the manual and some tutorials on its use and I will try your proposal.

[lee_griggs]

I just checked your render settings and you only have 1 diffuse (indirect) and 1 specular sample. Try increasing one and then the other to see which one improves the noise (probably both).

You can use AOVs in the ARV to isolate where the noise is coming from. Tutorial here. You can display the AOVs in the Arnold IPR Window.

I recommend going through all of the removing noise tutorials and sampling docs.

[piogil]

The render configuration that you have seen is not the final one, it is at a minimum to save time in the renders for the identification of the problematic light source.

Thanks for pointing me to the tutorials.