Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?message_id=2840942

Actually, in Poser black is the base level for displacement. To use it properly requires the use of a maths node so that mid grey becomes the base level so that black indents and white raises properly. A bump map does use mid grey as the base level, so that black gives the illusion of indentation and white gives the illusion of raised surfaces.

The linked thread has examples by diolma showing this, and also in the thread is a link to a thread showing the math node requirements for displacement to use mid grey as a base level.

I liked trans-mapped eyebrows personally too.