Glass Not Rendering Transparent

[v.aaron21]

Why is it that the glass material is not rendering transparent? I'm using the standard vray material without any adjustments. I placed sphere lights inside and when it begins to render you can see the light shining through the window but when it finishes processing the image the transparency disappears. Attached are images of what is happening. Is it a bug or a setting?

[matthewg]

Had a similar question in the general forums maybe this will help?

From my understanding if your using the out of the box vray texture on a 2D face the fog density is infinite, which then blocks out the light coming through from the back and your reflection takes over.

Hi matthewg,

The reason why your material renders black is its Fog Color.
The fog color is based on the color specified and the thickness of the object in the scene (the further the ray travels in the volume the darker color you'll see).
If your glass object has no thickness (is a single-sided surface) the fog density reaches infinity and leads to the dark shade that you see.
Simply adding a thickness to the face should resolve that.
If on the other hand you have to use single-sided surfaces (for windows let's say) you can create a Fake_Glass... from the Diagrammatic library category.

To have full control you can do the following from scratch:
> Black 'Diffuse' color
> White/Bright 'Reflection Color'
> 'Reflection IOR' on and equals 1.6 (or whatever you need)
> 'Refraction Color' set to a bright color for the tint
> 'Fog Color' - white
> 'IOR' set to 1
> 'Affect Shadows' on

You can also check out the material attached.

Regards,
Konstantin

I've attached the material file Konstantin attached for me also.

[v.aaron21]

Thank you so much. Your glass worked perfectly.

[gsinteriorsuk]

Why my glass is not transparent? I used glass material from the library but it doesn't work. It just comes out black. I also tried using Sketchup Glass material but it also doesn't work. Does anyone know what the problem might be?
I use Sketchup Pro 2018 and V-Ray 3.6.

[peerman]

If you are referring to the table. Change the fog color of the glass to pure white and try again. Or lower the fog distance of the glass material.
Hope that helps.

Best

[ilyabo]

Thank you - changing the color of the fog fixed the issue, but why is the v-ray stock material needs this in order to work properly? I'm frustrated it didn't work out of the box.

What about fog distance, where is this adjusted?

[peerman]

I meant the Fog Multiplier, sorry You could lower it to 0.001 for instance. Also make sure that your glass is modeled with the correct realworld thickness. Another thing could be reversed normals.

Best,