Hello,
I’m experiencing a rather complicated problem with object that need to have disabled shadow but at the same time be traceable for raytracing. I’ve got 4 different render layers and for some of them I could turn tracing off (for this object) but then I need it on one layer. I’m using one lamp and ambient occlusion all raytraced.
It was a while ago and I didn’t find any way to overcome this issue. But since it was a specific situation I’m sure that for most situations compositing with render layers would help. If you could describe me your scene with more details I’m sure we would figure something out.