Fig. 5. Graphical representation of the effect of changing various parameters on the predictive ability of thin-film Model 2. (A,B) The solid line shows Model 2 calculated from the variables as described in the text (extinction coefficient k of keratin=0.03, melanin=0.6; refractive index n of keratin=1.56, melanin=2.0). (A) The effects of increasing k of keratin to 0.06 (dotted line) and melanin to 1.0 (broken line). (B) The effects of increasing n of melanin to 2.2 (dotted line) and decreasing n of melanin to 1.8 (broken line).