Fresnel

Just need an explanation of what the fresnel node does. Thanks!

“Fresnel weight, indicating the probability with which light will reflect off the layer rather than passing through.” -From the Blender Wiki (http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/More)

Commonly it is used to create a layering effect when used as the Mix factor for Diffuse and Glossy shaders.

Thank you for your response! After reading the wiki, I have an idea of what the node does but I still don’t fully understand it. Ill have to experiment s’more.

Using fresnel to control the mix factor means that more of the 2nd shader is used when viewing the object’s surface at a steep angle and more of the 1st shader is used when viewing at a straight on angle. The higher the factor the steeper the angle has to be before seeing any effect from the 2nd shader.

hold a glass in front of you
look at it dead center and its totally transparent (ish)
now (might need to squint a bit) look down the side of the glass and its almost a mirror

hope that helps you understand it

Don’t mean to thread jack, but I hope related to the original question, what is the difference between using the fresnel shader, and the layer weight shader? They seem to do the same thing.

Layer weight’s fresnel output uses the same falloff as the fresnel node, but the mix factor is set as a simple 0-1 opacity instead of derived from an IOR.

Layer weight also has the facing output, which is just a simple blend from 0-90º