This paper is a continuation of our previous work [1] on the elaboration of first principles model for computing the BSDF (Bi-directional Scattering Distribution Function) of a cloth. New method realizes the idea of full statistical approach to cloth modeling with probabilistic goniometrical spectrophotometer. The main goal of the paper is to determine (based on original cloth model) parameters of probabilistic distributions used by stochastic ray tracing algorithm for implicit model of a cloth.