Hi guys,
I am working on my first interior scene, and I noticed that lighting & shading is quite a bit different from the usual product viz workflow.

scene:
- 4x32 FB
- openEXR
- IBL
- 4 areaLights in the windows connected with mia_portal_light
- all shaders are mia_material_x

first odd thing I noticed is blurry reflection quality - in specific when anisotropic is set to 0.1 to make metallic surfaces. (smoothness) quality is awefull.

I have added two pics. the object has applied a standard grey material_x. in first case it is not anisotropic, for 2nd pic the anisotropy is set to 0.1. in both cases glossyness is 0.4 and Glossy Samples are 64. additionally I plugged an envBlur into the shading group which makes no difference since most reflection comes from other object in the room. usually 64 samples is enough, but for this interior scene I´ve already cranked it up to 256 samples. unfortunately there is still grain! and - the more samples I give them glossy reflections the weaker the reflection color becomes, which btw is a major drawback. I´ve already talked about that somewhere else in this forum.

What I´ve tried so far and didn´t make any difference at all:

- increase IBL quality from default 0.2 to 0.5 (adding a string option in the miDefaultOptions)
- increasing AreaLight Samples from 20/1/10 to 60/60/60 (because at first I thought it is a shadowing artefact)
- increasing glossy samples until 256
- Shadows (renderGlobals) set to normal/sorted/segments
- FG filter 0, 1, 2

what made a difference but rendered for ages:
AA set to 1/3 and AA Contrast 0.02

because of resulting render time that low contrast setting really is no option.


my conclusion is:
imho it must have something to do with the glossy sampling...

any ideas?