Vray brute force glass problem with 2 objects !!

[Bigguns]

Vray Glass Brute problem.zip try the scene, just replace the HDRI, then do a render in brute force and one in irradiance map and LC and you will see the difference... can you tell me when it can be fixed? would help me enormously on the eyes

[Morbid Angel]

Ok, so what you are looking for is the material that has no refraction. Since when you have single sided material with refraction, vray will treat it as infinitely solid. There is no single sheet scattering or single sided refraction in vray, since its not physically accurate.

If you are after simple translucent material, just set the refraction to 1, and you will have no tinting or shadowing.

[Bigguns]

No,

I need it to have refraction IOR set at about 8 .. if no refraction I loose the effect I want ( it's for the lacrymal liquid.. when the iris meet the lower eyelids, it create a drker line at the bottom..check pictures on the net you'll see ) .

And why in IM LC it work and in Brute force it's darker? That's odd...

[Morbid Angel]

No,

I need it to have refraction IOR set at about 8 .. if no refraction I loose the effect I want ( it's for the lacrymal liquid.. when the iris meet the lower eyelids, it create a drker line at the bottom..check pictures on the net you'll see ) .

And why in IM LC it work and in Brute force it's darker? That's odd...

Ok it sounds like you are after something very specific. Could you please post a scene with another renderer like mental ray which produced exact result you are after, and also post a part of your production scene which shows the issue you are describing.

[Bigguns]

Simply, I think if it was working as well in brute force as it is in irradiance map, it would be just fine. I dont want to render in IR LC just for that.. since BF give me better result overall.. except for that detail. In my post 15 I am showing what you are asking for and in post 16 is the file.
I just want the 2d plane (without thickness ) with IOR at 8 lets say to render like in IR LC when using BF. because in BF instead of beeing transparent, it gets dark so far a lacrymal liquid it dont work well.. it does a grey line instead of beeing transparent like it should be, like it is in IR LC. ( bear in mind that I have IOR at 8, it don't show if you want in that pic because the BG is a uniforme color, but if I had put a bg with form you would have seen the raytrace IOR 8 in effect but it would had been harder to see that in BR it's more dark then in IR LC , so it's why I used a flat bg for that test )

[Svetlozar Draganov]

V-Ray does not calculate refraction from plane objects properly that is a fact and I am not sure if this is going to change in the future since there is no real objects with zero depth.
The result from IM+LC might look better or more suitable for what you are looking for than the one from BF+BF but it is still not physically accurate.
A large percent of the difference between both is caused by the GI caustics under the GI rollout, you could unify the result to a great extend by disabling Refractive/Reflective GI caustics but the difference won't completely disappear.

BF+BF+GI caustics:
IM+LC+GI caustics:
BF+BF-NO GI caustics:

[Bigguns]

Thanks for your reply. So it wont be fixed it will stay like that ? I thought there could be a work around to do but ok I will see what I do with it gonna try your tricks and see if its good enought.

[AC5L4T3R]

Op pls