The term 'Multi pass rendering' refers to rendering the light & surface details of a scene,not to specific objects. rendering light,reflection,specularity,shadows,diffuse materials,zdepth,ambient occlusion,self illumination etc,etc..all as seperate images Acadia..using this method you could render your shadow as a seperate image,this gives a lot of versatility in postworking your images there's generally no extra rendertime involved either as all these passes are generated while the main pass renders. Poser users can render multi passes using Gloworm (@ Daz)

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