When i create uv map in maya, import obj to zbrush, sculpt a bit , then create normal map, export it and render with mental ray or maya soft its peaches. BUT, create a uv map in 3.5 uv master, create normal map and export, maya hardware render viewport shows normal tangentnormalbumps, when render it with mental ray or software bumps are inverted, how’s that?
me found the solution, you should select the object go to mr approximaion editor in rendering editors /mental ray and create subdivision approximation, hit edit and take N Subdivisioms from 2 (default) to higher number (4 did it)