3ds max crash when enabling deph of field

[giovannigio]

hello there everybody. something strange going on here: i'm rendering a interior scene (sofa and a rug made with hair&fur). every time i enable depth of field in the vraycamera, 3dsmax crash after few minutes. when i disable depth of field, rendering goes well till the end. What's going on? 3ds 2015+vray 2.50.01. the problem is with the fur becouse if i enable depth of field and disable the fur, render goes well too. this happens with every scene, even in a simple scene ( rug, a box and one simple light)

 

thank you very much