Bad shading mesh in Iray

[Mattia5EC8]

Hi everyone,

I'm having a bad shading error in Iray render that i cant explain.

Is visible only in Iray, in paint mode i do not have any problem.

The mesh has benn exported from Blender with the faces smothed and in fact the same mesh in blender does not cause any shading issue.  Aloso if i give one more subdivision level to the mesh and i apply it, the mesh still give this weird shading issue in Iray.

As you can see the mesh is rather dense, so i cant figure out which could be the problem.

Thanks in advance to everybody.

[GeoffroySC]

Hi, 

Is displacement activated in Iray? Have you baked your height map in Painter?

This looks like what a height baked in Painter does in the rendering side of the soft as this bake was designed for catmull clark subdivisions. 

In any case, could you show us your mesh maps? 

Thank you,

Kind Regards,

Geoffroy SC

[Mattia5EC8]

Hi @GeoffroySC 

thanks for your help.

I'm sorry but i don't know nothing about Iray displacement, i never used, where i could find this function?

Sorry again for my ignorance but why i should enable the catmull clark subdivisions if in my render engine i wont use any subD for final render?

Here my mesh maps:

I actualy noticed a weird shading in the height map, as if it took some information from the low poly mesh. 

This is weird because i made the bake from an hig poly mesh at 8k with 64x supersampling

I have no idea of which could be the problem.

Thanks.