Yes, that's one of the standard articles on the topic. The problem in Poser 6 is that the lightprobe images are ordinary JPEGs. so they cannot be HDRIs. There are ways of getting 16-bit data into Poser using two 8-bit images, but getting the HDRI image to start from is hard. You're talking about multiple digital images, shot by a camera on a solid tripod, with varying exposure settings, or a very special camera. [Brief tech note: the shader engine is working at much height precision than input texturemaps, both brightness range and the UV-resolution, and you can use scale/offset on an imagemap to get the high local resolution. But brightness, that's harder.]