Hm.  I seem to be having an issue with 3D motion blur during my animations.  When it's on, there's artifacts that appear on my models that aren't there while the motion blur is off.  See below:

As you can see, there seems to be a black smudge on the left side of the nose. as well as a angled line (though it's almost not visible in this picture) on the right side of the lower lips.

I've tried many different rendering options and, short of abandoning 3D motion blur, have not been successful at getting rid of these artifacts.  During an animation, they seem to jump and dance all around the models.

What is causing them?

Thanks a bunch!

Hm that's a new one O.o

Have you tried with 2D motion blur? 

I haven't used Motion Blur up to now, but I will give it a try. Which version of Poser are you using? What kind of lighting?

I'm using two lights in this scene.  The main light is an infinite light off to the left of the figure.   Shadow Blur Radius: 10, Shadow Samples 38, Shadow Min Bias: 0.5, Atmosphere Strength: 0.01 (I played with these amounts to see if it would get rid of it and it didn't). No connected nodes, just a yellowish color (255,255,200) to the Color entry.  The other light is a spotlight off behind the fence primitive; shadow blur radius: 2, Shadow Min Bias 0.8 Atmosphere Strength: 0.01, also no nodes attached, and a slight purplish color (201,177,237) in the Color entry.

It's a relatively simple scene.  A few props parented to the figures (there's another figure off camera), a couple of primitives and some displacements on the primitives.

I zoomed far in on one of the artifacts and it appears to be as if it were part of the texture (it's in the same place no matter where the camera is) and seems to be limited to a single polygon.

Ray traced or depth mapped shadows? Poser pro 2010?