I think you'll potentially run into problems using raytraced shadows with transmapped hair - I had problems with light casting shadows only of the hair and not the head, which lead to odd shadows across the body.

I'd use depth mapped shadows. Learn what the parameters settings do. Increase the shadow map size to 512 or higher, get optimum results focusing the lights using shadow lite cams, and maybe reduce the shadow blur radius. Lower the bias settings (you can go very low with depth mapped shadows). Also, render settings can make a whole heap of difference, especially Minimum texture sizes with using transmapped hair.

Do some forum searches here for things like Transmapped Hair, Depth-mapped shadows and Shadow lite Cams. There have been some really interesting threads.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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