Well, I would say a few things. Poser isn't exactly a world-class render engine ;). It wants to be but it's not. However, you have options in Poser. You can export to Luxrender or you can use a render engine like Kerkythea. You can even export (as obj) to Blender and use Cycles - all better renderers, but they have their drawbacks as well. You can do postwork, but like anything else, it takes skill too. Each renderer has its advantages and it's faults.

Laurie