> Quote - 4/30/08 > > If Poser Pro now saves the Gamma setting for each image, I wonder if the programmers provided a Python variable for this setting? If so, maybe a script can be written to change the Gamma setting on images attached to certain channels of the root node? > > Does one need to change a gamma setting for a non-image based node plugged into bump, displacement, or other root node channels? > > LMK

Well I had thought that gamma only applies to images. But now I'm not so sure. I've done a little testing and there is more going on.

It seems to be that any color channel value that you enter into a node - any node - is modified by the gamma settings. I suppose the thinking was that you are choosing colors using as you perceive them on the screen, and that mathematically what you see and chose need to be adjusted to linear color space.

Consider the attached image. I'm using a tile node. One tile is orange: RGB(192, 128, 64) and the other is blue: RGB(64, 128, 192). It is attached to the Alternate_Diffuse input, so that exactly those colors are sent to the render, without any lighting calculation.

I have gamma enabled at 2.2. The preview and the render produce exactly those colors. Since the final render is "output gamma" corrected (raised to the power 1/2.2) , then we must conclude that those node colors were "input gamma" corrected (raised to the power 2.2). If this were not the case, the rendered colors would have been brighter than what I entered into the node.

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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)