Its been a while since using Houdini and 13 in particular. With a very simple set up that I have made I keep getting a white speckle / noise when using reflection and refraction. Breaking out the render with the new component system I am unable to see it in any pass but its in the beauty.
Ive made a simple test scene that shows it. Smooth surface, no displacement , so min and max ray samples I thought would fix it, but no matter what I cannot get rid of it . It doesn't help not being able to isolate the issue into an image plane out put to get at least a start point to debug . Any ideas ?
refraction speckle in renders
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- circusmonkey
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- are2d2
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- circusmonkey
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- eetu
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Hmm, the noise is quite resilient indeed. It does go away if you bruteforce a lot of samples, but none of the sampling settings anywhere made a dent. BTW, while chasing this I saw that the Reflection and Refraction Quality settings are not hooked up to anything in the base lighting model in the materials..
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- are2d2
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- are2d2
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- circusmonkey
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- are2d2
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Hmmmm, maybe… before you do that - take a look at this.
Try turning off the environment light and then doing a render, look at how noisy the indirect reflection is… (indirect_reflect__1) and the indirect refract (indirect_refract__2).
then turn off the ‘Reflect Objects’ in the Base of the Reflect tab in the shader…. I haven't had a chance to dig into the shader yet but I think maybe the noisy indirect reflection is getting multiplied with or sampled in with the refraction? My shader writing is not so hot, but I'll try and go through the shader, but take a look at the indirect reflect (indirect_reflect__2) and indirect refract (indirect_refract__2) images - do you know how to clean up the indirect reflection? I think that would tidy it up or there is an issue with the interaction between the indirect reflection and indirect refraction…
I'll try taking a closer look at the shader…
Try turning off the environment light and then doing a render, look at how noisy the indirect reflection is… (indirect_reflect__1) and the indirect refract (indirect_refract__2).
then turn off the ‘Reflect Objects’ in the Base of the Reflect tab in the shader…. I haven't had a chance to dig into the shader yet but I think maybe the noisy indirect reflection is getting multiplied with or sampled in with the refraction? My shader writing is not so hot, but I'll try and go through the shader, but take a look at the indirect reflect (indirect_reflect__2) and indirect refract (indirect_refract__2) images - do you know how to clean up the indirect reflection? I think that would tidy it up or there is an issue with the interaction between the indirect reflection and indirect refraction…
I'll try taking a closer look at the shader…
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- circusmonkey
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