Quote - Here's a strange thing. Cath was talking about IBL Contrast and we have to guess at what it really does.

The previous render was with IBL Contrast = 1.

I lowered the contrast to .75 and strangely the contrast increased - not at all what is expected.

Setting it to 0 causes a very slow black render.

To this theme, it happen that it turn to black b-c the Light probe hdr was NOT tone mapped before exported to hdr format, mean the contrast was to low and the level of the luminosity was to high, the Luminosity of the tone mapped HDR should be at zero, and the contrast at 1.0
before exporting it to the final hdr format.. the tone mapping is new so I guess all the old hdr maps have not what we need.. if the maps was right, you should get exactly balance of the light and shadows and by setting the intensity lower in poser material room the hdr map will  set the light slowly down, at first the elements and at the end the sky would get dark..
after changing the contrast to zero, there would be not shadows in the scene and one thing what stay over is pure luminosity... I know what i am talking about ... ~~smile~~

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