VRAY rendering multiple layers of glass

[sirius_aor]

Hello, good morning everyone,
First time I post in a forum about this, I usually find the solution to my problems in other people's questions.

But this is way over my head.

I'm working on a render of an acrylic artifact, where from one perspective you see multiple layers of acrylic overlapping.

The problem that I can't solve is that having multiple layers, the back tubes become gray, and the more layers of acrylic, the grayer it looks.

I have been playing with the IOR values in both reflxion and reflxation but I can't find the solution.

I know that several layers of glass end up looking opaque in reality, but this doesn't look like what it is.

If anyone has a solution I would greatly appreciate it.

Thanks






This is the real stuff, i need to improve the design and the internal reflections are the most important part of the improvement.

[fixeighted]

This is maybe the reflection and refraction depth, as if it's too low it tends to cause issues with transparent stuff.
I don't use SU but the parameter should be called the same I think, so look for 'trace depth'.
Also if you can set the material to 'reflect on back side' then that can greatly improve realism.
Of course, including tiny chamfers to everything with a quick vrayedgestex will always help with realism and nice highlights etc.

[sirius_aor]

Thank you very much, will look for this options!

[nikoleta.garkova]

Hi sirius_aor,

As fixeighted has kindly noted, you could try the Max Depth parameters of the materials - you can find those settings when you enable the Advanced Settings of the VRayMtl; see screenshot attached.

Alternatively, you can override those globally by going to the Render Settings > Render Parameters > Optimizations > enable Max Trace Depth (screenshot attached).

You could also send us the project files so we can have a look and come back with some solutions/feedback. Thanks!

[sirius_aor]

Hi

This parameters totally solved the problem! Thank you very much!!!

I have never use the Vray Edge texture, in chaos documentations says that i have to put it in bump channel (https://docs.chaosgroup.com/display/VSKETCHUP/Edges) , what would be the parameters? would like to know more if that's possible!
ight now i am getting the render out will let you see the results

Thank you again both of you!

[sirius_aor]

Everything looks good on the cristal clear, but now i am getting some noise on the base of the artifact.

will try to play with the Reflection IOR, dont know if the round edges are affecting that.

[fixeighted]

That does look a lot better, though maybe it would benefit from whatever reflection map having more contrast to introduce more blacks and make highlights pop more.

Artifacts? Do you mean at the base of the main object? If so, then that looks like it may be geometry issues. It could also be that the object is intersecting the floor.
It could just be the effect of refraction on the rounded corners, so you could test by turning that off. If it is that then possibly try chamfering those edges rather than using the fake method, just to troubleshoot.

Or, it could be the 'affect back side option', so try turning it on and off to see if it fixes it.
Certainly in Vray5 for Max there is an issue with the brdf when this option is enabled.
To fix it you need to choose blinn I think, as microfacet and phong will both shade it incorrectly.

EDIT: I just built this to test it and the base 'artifacts' are just a result of reflection/refraction it seems

[sirius_aor]

Thank you for all your help, i will keep playing with values!

[sirio76]

Try to use correct values for reflection and refraction IOR.