Hello today I got this picture from the marketplace testers. It's no problem to see what the problem is but I have no idea where it comes from. Something is wrong with the polygon which makes this strange shading. The polygon is not always lighter most of the time it is darker then the rest of the modell.

I made the object in 3dMax where it looks perfect. Even in 3dExploration it's still fine. Only in Poser this error is visible and even then not all the time. It depends very much on the light.

What happend here and how can I fix this ?