topic Re: Emission in standard surface in Arnold General Rendering Forum

Emission in standard surface

rico — Wed, 19 Feb 2020 16:27:29 GMT

Sometimes I have to use the emission in set standard shader to light a part of the scene. Then it males no difference to set the emission to 100 to to 1000. It's not getting brighter. Is there something limiting the emission of the standard shader on higher values?

Re: Emission in standard surface

rico — Sat, 22 Feb 2020 13:10:46 GMT

Can someone help? Maybe I don’t have explaind my problem well.

Re: Emission in standard surface

Stephen.Blair — Sat, 22 Feb 2020 16:53:35 GMT

The surface itself should be getting "brighter"
The pixel values on the surface will be way over 1,1,1

Other objects in the scene use diffuse (indirect) sampling to get a contribution from the emissive surface, and that is clamped to 10 by default.

Re: Emission in standard surface

rico — Sun, 23 Feb 2020 11:14:37 GMT

Is this the setting for clamping diffuse samples? By default it's switched off. Or is there another setting?

Re: Emission in standard surface

Stephen.Blair — Sun, 23 Feb 2020 11:38:26 GMT

The UI control is disabled, so you get the default of 10

if you want a different value, enable the UI and change the avlue.

Re: Emission in standard surface

rico — Sun, 23 Feb 2020 18:19:07 GMT

Thank you. This hint is very helpful.

Re: Emission in standard surface

rico — Mon, 24 Feb 2020 07:00:32 GMT

I did some tests and I changed the indirect sample clamp. But the brightness of the emission does not change.

Re: Emission in standard surface

rico — Mon, 24 Feb 2020 07:02:17 GMT

Here I set the emission to 100 an the sample clamp to 1 and 100. There is no difference in brightness.

Re: Emission in standard surface

peter.horvath6V6K3 — Mon, 24 Feb 2020 11:07:43 GMT

There's a bug in the plugin and the indirect clamp is not exported properly now. It's gonna be fixed in a next release.

Re: Emission in standard surface

Stephen.Blair — Mon, 24 Feb 2020 11:17:34 GMT

User options workaround:

Re: Emission in standard surface

peter.horvath6V6K3 — Mon, 24 Feb 2020 11:27:48 GMT

As a workaround you can set the indirect_sample_clamp as a user option in the render settings: