You can indeed export Poser RIB files which can be rendered in BMRT. I believe 2.5 was the last version of BMRT available as freeware but there are acouple of other freeware Renderman type renderers available. As I recall, you have to do a search and replace on the RIB file to change the line endings to the Unix style BMRT expecta and possibly change the textures to TIF. Don't know of a utility for RIBs, but there is one to use PZ3s with POVRay.

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