Shadow weirdness

[duke2]

I've only come across this a few times, and yes I can fix it with the sun shadow bias, but then light goes where it shouldn't. Anyone have any tips?

[Sascha Selent]

Origin?

I've only come across this a few times, and yes I can fix it with the sun shadow bias, but then light goes where it shouldn't. Anyone have any tips?

Just a shot in the dark: I sometimes get problems when objects are far away from the origin...

...seems to be a large outdoor-scene...

[vlado]

You could subdivide those rocks a bit to smooth the geometry.

Best regards,
Vlado

[Morbid Angel]

looks like shadow bias is not working...if you cant get rid of those artifacts by adjusting it?

[duke2]

The rocks are far away from the origin. MA, shadow bias does work but then I loose "correct" shadows. ie. something like VRayFur wouldn't even cast shadow.

[mcvltd]

I was getting some funky shadow results similar to this when I was duplicating the max standard camera in the scene. I changed to vray phys cam and the problems dissappeared. If you're already using vray phys cam then just ignore me...

[Morbid Angel]

just subdivide those meshes then as vlado said.

[Da_elf]

are you raising or lowering the shadow bias?

[vance3d]

I'm having similar results using a vray sun. I've been able to trace some of the problems to the fog level. It seems that if it were set to anything other than 1.0 with white as the color, I would get those kind of shadow artifacts. I'll have to send along some test images on Monday.

V Miller

[vance3d]

Here is the shadow artifact I am experiencing. My scene is lit with a vray sun and sky and both renders are using a vray material with the default settings. The only difference is that the fog color is different. I ran into this because my real shaders for this object were using translucency so my material included refraction and fog.

V Miller

[vlado]

Translucency tends to show this for low-poly objects; the normal phong interpolation does not work in this case, as the fog depends on the length of rays actually traced under the given geometry.

Best regards,
Vlado

[vance3d]

Are you referring to the bdrf in this case? Because the default is blinn and this object is also pretty heavily turbosmoothed. And the material I have in my sample has no refraction or translucency applied.

V Miller