VrayScatterVolume not working correctly with BlendMTL

[LudvikKoutny]

Hi,

I need to create murky water that needs to bounce some light back to the camera, not just absorb it, so I chose to go with VrayScatterVolume to avoid painfully slow VrayMTL sss. I've tried to follow the approach described here: https://docs.chaosgroup.com/display/...me-SampleUsage however I am not having much of a luck.

The problem with the approach in that guide is that it relies on the coat material, which represents the surface of the liquid, to be blended only by 50% with the base scatter volume. This means with this approach, my water reflectivity effectively drops by 50%, and it shows. It just looks bad.

When I try to set water layer in BlendMTL to 100%, the scatter volume inside turns completely black, despite affect shadows in refractive water material being enabled.

So right now, I have no idea how to do that water. ScatterVolume relies on workflow that makes my water significantly less reflective, and VrayMTL SSS is just slow. And so is VrayEnvironment fog, especially when used in combination with high poly meshes as gizmos.

Any help will be appreciated.

[Raven]

Is your reflection coat material 100% refractive? It would need to be as it is creating the water, and you volume scatter is creating your suspended particles in the volume.

[nikolay.kusht]

When I try to set water layer in BlendMTL to 100%, the scatter volume inside turns completely black, despite affect shadows in refractive water material being enabled.

If the water material is refractive, the VrayScatterVolume should be visible despite that you have set the water layer in VrayBlendMtl to 100%. Could you share few screnshots of your resulst along with the materials properties that you are using. Do you have any reference images?

[LudvikKoutny]

If the water material is refractive, the VrayScatterVolume should be visible despite that you have set the water layer in VrayBlendMtl to 100%. Could you share few screnshots of your resulst along with the materials properties that you are using. Do you have any reference images?

It's a simple scene lit by just one textured domelight.

Here's an image showing ScatterVolume only, ScatterVolume+Water Material with 50% blend, and ScatterVolume+Water Material with 100% blend, in order from left to right:

Here's screenshot of the ScatterVolume:

Water:

And BlendMTL: