Bagginsbill's Free EnvSphere package.  not hard to use if yer familiar with hdri used as lite source in poser scenes.  couldn't find free equirectangular moonlite hdri during google search.  dosch has some, but "dosch skies" costs $$$ IIRC.  is possible to create simple hdri in APS with brite blue area where one desires moon.  second choice (easier): IDL render with hi-res ball (blue ambient as lite source), as ment. abv..  third choice (easiest): use dim blue inf lite with IDL.  fourth choice (wrong): poser 4 render with blue inf lite.