it does not have a scale, because it is a fake effect
Just too big threshold, in Vray convenient because there control integers 0-100 or more. For example, in value in Vray 1 is roughly comparable with the value of 0.01 Corona
The work is not very convenient, continuously put fractional numbers. If it is impossible to bind to specific units of measurement, the threshold can be done 0-100?
It would be logical to me seems like 0% 10% 30% .... 100% 300%