Trace Refractions– Enables refractions for the current material.
Max depth – The number of times a ray can be refracted. Scenes with lots of refractive and reflective surfaces may require higher values to look correct. See the Refraction Depth example above for illustration.
Affect Channels – Allows the user to specify which channels are going to be affected by the transparency of the material.
Color Only – The transparency affects only the RGB channel of the final render. Color+alpha – This will cause the material to transmit the alpha of the refracted objects, instead of displaying an opaque alpha. All channels – All channels and render elements are affected by the transparency of the material. This option is not available for V-Ray GPU.
Dispersion – Enables the calculation of true light wavelength dispersion.
Dispersion Abbe – Allows the user to increase or decrease the dispersion effect. Lowering it widens the dispersion and vice versa. See the Dispersion Abbe example below for illustration.
