In addition to the points already raised in this thread: The amount of stuff, walls, people, props, you have in a poser document will affect the strength of the shadows. Each light has a dial called "Shadow" which can adjust the strength of shadow from that light, try increasing the value on this dial, if the light is a spotlight it should be easy, If its an Infinate light you may need to double click on the dial and set "Max Limit:" to 9 first. If the edges of the shadows become ragged or sawtoothed increase the Map size.