Strange shadows in VRay render

Johsan

I have this problem where I get this strange shadows when I render my image. I use 3D Studio Max, VRay render and the render setup i have image sampler: adaptive subdivision and antialiasing filter area. I use VRay lights only and VRay Physical Camera.

cupsster

check GI sample density also if you are using Light Cache meke sure using world with small enough cell and if you does not checked show samples by accident..

cupsster

your GI is for sure lacking detail cause at top right corner you have stretched cell = > check "check for sample visibility" = will increaste time a little but should clean up some mess

Johsan

I have "sample lookup" = density-based(best) and have cecked "check sample visibility. What should I do with the cells? And where do I fix that?

I have current preset Medium.

cupsster

check if scale of scene is ok and also system and display units.. if not use Tools > Rescale Units tool..
Check for http://www.mintviz.com/blog/vray-render-settings-for-interior-visualisation/

Johsan

I followed the tutorial and when I render the image is just black after 15 minutes. It says that it´s building light cache but how long does that take?

cupsster

check if your camera is not beyond some wall.. if it is black you does not have checked show progress at Ligh Cache (LC) also Irradinace Map (IR) have this checkbox wich is unchecked by default... need to be checked to see progress.. please consult cgarchitect.com forum if this is not related to game art

Johsan

Tank you for the link! I asked my question there and they told me to set the Hemispherical subdivisions to 50-60 and the Interpoation Samples to half the Hemispherical subdivs. Light Cache should be at least 1000. For interior rending they recommend to use Adaptive DMC. I set the Global subdivisions Multiplier 2-3 and the DMC Min Samples to 16. I also use Catmull-Rom. Now there´s no strange shadows

cupsster

Yeah, I know, I'm also member there..
Cheers.