Tagged 'zap's mental ray tips'

Dispersion

12 votes

Dispersion is when different wavelengths refract differently. I guess the most obvious case of this is a rainbow.

Real sunlight is a spectra containing basically an infinite number of wavelengths at once, and each of the different wavelengths will refract slightly differently... i.e. when a sunray hits a surface, one would (in principle) need to trace an infinite amount of rays around the scene to get the "real" effect.