There is a known bug in Poser 6 reflections and refractions. This might be causing the blurriness you are seeing. I was getting some ugly distortions in refractions in Poser 6 that I wasn't getting in Poser 5 so I sent an email to Curious Labs about it and sent them a picture showing the problem. They replied that they are aware of the problem and that the service release will fix it. Cross your fingers.