I’ve been messing around with the Fresnel and IOR settings to get a better understanding of how they work. I don’t know if this is of any use to people but I thought I’d share the results of my experiments.
basic set up was a camera, large smoothed UVSphere and a cube positioned behind the UVSphere
- Changing only the Fresnel setting:
- Changing the fac setting, with Fresnel set at 3 different values:
- Changing IOR values (with Fresnel set at 3, fac at 2)
- Changing the camera angle so it is no longer in line with sphere and cube. (Fresnel 3, fac 2)
As a footnote: I assume the Fresnel shader is named after Augustin Jean Fresnel (1788-1827) who is famous for his work with lighthouses, the Fresnel lens and working on the wave theory of light.
He published his first paper in October 1815 on his wave theory of light and made a first attempt to explain the phenomenon of diffraction