Yep, the streaking is caused by Poser rendering a double-sided object. It's interesting that I rendered the images for my tutorial in Poser 5 and I didn't get the streaking. I wonder if it's the light set that I used or if this is another bug in the Firefly renderer.

I'll have to look at my tutorial and tell people to use the BOX instead of the one-sided square. ;)

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