On this page (instructions)

In Advanced mode, load a panoramic image in the "Panoramic Image" node.

You can load HDR images or LDR images.

Here I have chosen an HDR image - the pond image that comes with Poser 7.

 

Above the Panoramic Image node is a node called Gamma In. You must tell the shader what the gamma is of the incoming image. Ordinary photos have Gamma In = 2.2 (usually) but HDR images have gamma = 1.0. So for HDR set Gamma In to 1.0.

 

Again:

 

HDR Image -> Gamma In = 1.0

LDR Image -> Gamma In = 2.2

When you set the Gamma In correctly, the Image preview (at right here) will still be weird, but the final preview should look normal.

---

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)