Good catch, Laurie!

     I think the problem is due to the polys shadowing each other, and even an infinitely small shadow minimum bias can't relieve it.

 

edit:  Cross-posted with Sam;  anyway, I think it's due to two polys sharing the same space -or at least intersecting- making it impossible to get a min bias to fix it.

     Have you tried adjusting the shadow minimum bias?  If the polys are close, but not sharing space, that may indeed fix it.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

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