In Herbst's tests platinum reproduces 19 steps of the step tablet in a manner that is clearly discernable to the human eye, while Azo reproduces 18. However, the density of the platinum print extends from 0.13 to 1.47 (reflective density range 1.34), whereas the Azo density extends from 0.15 to 1.92 (reflective density range 1.77). The tonal range reproduced is virtually identical, but the reflective range of the Azo is just over two stops greater than the platinum print in this test. The extended reflective range of the Azo is in the blacks, which are much deeper than the blacks in platinum/palladium. However, the high values of the platinum/palladium print have more delicate gradation than the Azo print.