Maya Vray 32bit displacement issue

#1

Hey, I’m trying to render out a 32 bit displacement map at the moment for a character bust of mine. I haven’t used 32bit displacement before and I’m having a few issues. I’ve followed a tutorial exactly on how to use 32 bit maps however it seems as though the “negative colors” attribute for the displacement maps aren’t working. Everything with the displacement seems to be working fine apart from the recessed areas. Any ideas on what the problem is? here’s a pic:

#2

Just in case anyone else has the same issue as this, I followed this tutorial using a luminescence node with a plus minus average as a workaround. Bit tedious but it works.

http://www.disopolis.com/wordpress/2012/part-4-multi-tile-displacement-mappingshader-assignment/