•Uniformly partitioning the displayable intensity range into equidistant arithmetic intervals is wasteful
•Each intensity should differ from the previous by a constant ratio.
•I0 = minimum non-zero displayable
intensity
•In = maximum displayable intensity = 1.0
•I1 = r I0, I2 = r I1 = r2 I0 , I3 = r I2 = r2 I1 = r3 I0
•In = rn I0 Þ r = (1/ I0)1/n