Getting Unwanted Artifacts

[leejk]

Hi,

I'm trying to render just the shadow of my scene, so I have set all of the layers to be invisible to the camera. When I render tho, the resulting images displays artifacts that appear to be from objects casting shadows on each other, or some other problem. I've made sure that all scene objects are set to render by layer also. I switched the scene over to mental ray and was able to render it with no issue, so it seems to be VRay specific. Does anyone have any ideas as to what might cause this?

thx

[Dariusz Makowski (Dadal)]

Do you have embree on ?

[cheerioboy]

I believe for this you want to crank up your Max transp. levels in the V-Ray:: Global switches
Default is 50... try 100 or 500. Until the artifacts go away.

[vlado]

cheerioboy is right, try increasing the max. transparent levels.

Best regards,
Vlado

[Morbid Angel]

We get this all the time, when complex objects are with prime vis off, however its not an issue since when you composite, your beauty always covers these artifacts, so we don't even bother fixing them

[leejk]

I believe for this you want to crank up your Max transp. levels in the V-Ray:: Global switches
Default is 50... try 100 or 500. Until the artifacts go away.

Thank you, that seems to have gotten most of it out. I'm still seeing some "ghosting" present tho even after cranking it to 1000.

[vlado]

Does it go away if you set the secondary rays bias to something like 0.001?

Best regards,
Vlado

[leejk]

Does it go away if you set the secondary rays bias to something like 0.001?

Best regards,
Vlado

No, I tried adjusting that setting as well.

[vlado]

Hm, then would it be possible to send us that part of the scene to vray@chaosgroup.com to see what can be done about it? It's possible to increase the transparency levels beyond 1000 through MaxScript, but it seems that there is also something else going on.

Best regards,
Vlado