OTOY Forums

Is this a known issue? I haven't seen it written anywhere. I've got a room with windows made of specular material at 100% opacity (but are still basically transparent). The camera is looking in from outside. There are lights inside, but I don't want the camera to see them. So I select Unseen By Camera. But the camera can see them. If the camera is inside, they're unseen. If the camera remains outside, but I reduce the opacity of the specular material, the lights gradually disappear, but at different rates depending on their position.

If I do the same test with Glossy Material with only 50% or 10% opacity, the lights are always unseen. But Specular Material looks much better as glass, especially at 100% opacity.

The glass geometry doesn't have any thickness and has Double Sided selected in the Surface Editor. Is this a problem?

It doesn't matter whether Affect Alpha is selected in the Spectral Material node. Same effect either way.

I think that it is a limitation of the renderer. The lights are hidden to the camera rays and the opacity parameter doesn't change the nature of the ray, it is camera ray even after pass through the object. But if the ray pass through a specular object, it becomes a refracted ray, it is not anymore a camera ray, and this is why it is not hidden to the camera.

As far I know other render engines have the same problem, you need to hide the lights also for refracted rays, but this feature is not yet available in Octane.

-Juanjo

Could you use the visibility of the lights SHAPE to hide it for your situation? I do this a lot in my setups. The light still affects the scene with illumination as well as reflections in glossy materials but the shape of the light does not actually show up in the render...

3dreamstudios wrote:Could you use the visibility of the lights SHAPE to hide it for your situation? I do this a lot in my setups. The light still affects the scene with illumination as well as reflections in glossy materials but the shape of the light does not actually show up in the render...

Yes, that did the trick, thanks. I had used that previously but for some reason I developed a blind-spot to it this time!