What is the difference between R-fit v4 and R-Fit LIVE?
R-Fit LIVE requires the refractive index to be input, then it automatically fits the incoming data to provide rate and roughness. R-Fit v4 cannot provide data in real time, but does not need an accurate value of refractive index to be put in. Both have to have ranges of values for the rate and the roughness in order to work.