RADIOACTIVE

Sat Apr 07, 2012 4:43 am

Funny thing happening today
when I used HDRI for texturing as diffuse color in exr format , it started to emitting light like emitter , but the emitter was set off .. it was interesting and I suppose it is a bug .. the funny thing was that the gamma slider was used for power the intensity of the light , and it ended with radioactive skin emission ..

this give me a nice idea to plug some full spectrum HDRI into my light panel props for faster rendering of the light emitter in place of using the blackbody emission

Cath

Sat Apr 07, 2012 6:48 am

Thats not realy a bug. More a effect of a pure hdr image itself.
Where 8bit images have max 255 values per channel, will have a hdr image much more.
This more will have also an intensity information.

The effect was shown for a while and was used before the emitters are implemented in Octane.
So much i know will have an image with a real emitter lesser noise. Maybe because a emitter becomes intern more samples...

face

Sat Apr 07, 2012 12:33 pm

This will happen if the HDR file contains values larger than 1.0 (= 255 in a 8-bit LDR image). The diffuse input defines the proportion of incoming light that gets reflected, e.g 0.5 means 50% of the light gets reflected, the other half gets absorbed. If this input is more than 1.0, instead of absorbing part of the incoming light the object will multiply the incoming light.

--
Roeland

Sat Apr 07, 2012 3:26 pm

Thanks Guys ..I never saw this in any other apps when used on the object surface so that is interesting ,and well the gamma powered the effect much more intensive , also noticed very nice spectrum effect of this, , it is more noisy and take little longer to clean up but the rendering time regarding to light emitters is just 1 min in difference after my test of both however the global illumination effect is much more stronger as emitters create more of a coat effect on the surface blocking most of the radiance emitted from the surfaces that are lit with the emitters , but different story with the hdri maps , what can be interesting to use in some light situations as IBL