Specular node Reflection parameter question

Generic forum to discuss Octane Render, post ideas and suggest improvements.
Forum rules
Please add your OS and Hardware Configuration in your signature, it makes it easier for us to help you analyze problems. Example: Win 7 64 | Geforce GTX680 | i7 3770 | 16GB
Post Reply
Whichway
Licensed Customer
Posts: 37
Joined: Thu Mar 11, 2010 10:32 pm

I'm trying to be sure I understand the intent of the Reflection parameter. For a simple, ideal, clear dialectric, like perfect glass, I would expect the ratio of transmitted to reflected light at a surface to be determined completely by the index of refraction via the Fresnel equations. Modifying the transmitted value makes sense in the presence of impurities that absorb some of the Transmitted light in a color dependent way. Impurities on the surface, finger prints, for example, could lower the amount of Reflected light. That all makes sense to me; my only question is with the value of the default Reflection parameter. Isn't 0.5 rather low for something that's most likely going to be something like glass? [Of course, I know the Reflection channel could also be used with an image for doing environmental reflections without raytracing. My apologies if that's too much stating of the obvious, but I'm fairly new at this stuff.]

Whichway
Win 7 64 Ultimate | GeForce 8600M GT | nVidia 197.16 | Core 2 Duo T9600 @ 2.50 GHz | 4 GB {being retired}
Win 7 64 Ultimate | 2xGeForce GTS 250 1GB ea. SLI | nVidia 196.21 | ASUS P6T | i7 920 | 6 GB
User avatar
radiance
Posts: 7633
Joined: Wed Oct 21, 2009 2:33 pm

The reason why i put it at 0.5 by default is so that it creates less fireflies.
When MLT is finished and available i'll put it back to 1.0 by default.

Radiance
Win 7 x64 & ubuntu | 2x GTX480 | Quad 2.66GHz | 8GB
Whichway
Licensed Customer
Posts: 37
Joined: Thu Mar 11, 2010 10:32 pm

Ah. Thanks!

Whichway
Win 7 64 Ultimate | GeForce 8600M GT | nVidia 197.16 | Core 2 Duo T9600 @ 2.50 GHz | 4 GB {being retired}
Win 7 64 Ultimate | 2xGeForce GTS 250 1GB ea. SLI | nVidia 196.21 | ASUS P6T | i7 920 | 6 GB
Post Reply

Return to “General Discussion”