SPECULAR
Reflection Tint
Colour multiplier for external reflection. It should be used sparingly, as a non-white value breaks physicality.
Transmission Tint
Colour multiplier for rays going inside the medium (covers external transmission and internal reflection). It should be used sparingly, as a non-white value breaks physicality.
The prefered preferred way to define the colour color of a dielectric is through the Interior attributes right below.
Fresnel Mode
Switches the Fresnel between Artistic and Scientific parameters.
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The Scientific mode provides an index of refraction for each rgb RGB component. Note that IOR is only used to calculate the reflectivity value used by the Schlick approximation.
When reflectivity90 is 1, then both modes achieve identical results, as one can be mapped to the other.
Reflectivity
Colour reflected by the surface in the normal direction. Corresponds to specColor.
IOR
Index of refraction (often denoted by "eta"), defining the amount reflected by the surface in the normal direction, and how the rays are bent by refraction. A separate value can be specified for each colour color channel , if desired.
Reflectivity 90
Colour reflected by the surface at the grazing angle. Should be kept at 1,1,1 for most materials. Corresponds to specColor90.
ReflectivityProfile
The inverse of the exponent to use for Schlick
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Micro facets or tiny bits of roughness can scatter light in a way that has a blurry result. The less rough, the mirror-like, and smooth/slick the material may look. High values will simply look diffuse.
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Anisotropy Parameters
Anisotropy
This control determine determines the direction light travels, more forwards (positive) or more backwards (negative) toward the light source when it travels through the object.
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These parameters control the bulk of a dielectric material. When you think of what makes a glass object look like it does...the color and clarity, it's the absorption.
Absorption Color
This is the Interior volume absorption color. This allows It is defined as the negative logarithm of the extinction coefficient, with values between 0 and 1, such that the object and shadow to be correctly tinted. A value of white is no absorption, no tint or shadow. A black value is totally opaque, black and solid. If a color is supplied and this is the top of a Lama Stack, it will be the coating coloritself and its shadows are tinted proportionally. If set to 1, there is no absorption, and if set to 0, the object will be completely opaque. Note that for single scattering to kick in, the value must be inferior to 1. This value will also act as a coating color when this node is used as a top layer in a stack.
Absorption Radius
The maximum reach in scene units of light before it is absorbed.
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Defines the Arbitrary Output Variabe Variable (AOV) name for the resulting Light Path Expression (LPE)
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