This diagram from the Pixar article is EXACTLY the math used in Poser, and what I have been showing in my calculations.

Incoming JPG, PNG, and other 8-bit sRGB images, and material room sRGB color swatches, are assumed to be encoded with gamma = 2.2. They must be converted to linear.

Incoming EXR or HDR images are already linear. They were designed for use in computer graphics. So they were designed to not require extra steps before we can use them.

If you ask Poser to produce an HDR output (render option) and save as EXR or HDR, it will NOT apply the final gamma correction. The linear values will be recorded straight into the file.

If you ask Poser to ignore gamma, it will do the same for sRGB images such as JPG or PNG and that is just wrong. When you display them, the display software assumes they are already converted to gamma 2.2 encoding, and since they are not in that case, they look darker.

All the linear numbers besides 0 and 255 mean something else and are represented as something else in a gamma encoded image.

---

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)