For qualitative and diverging palettes the challenge is even harder. The way that we perceive changes in colour intensity is another one of those complicated, difficult aspects of visual perception that can lead to mistakes. In particular if we space out an even set of lightnesses according the RGB colour values, the steps between these lightnesses are very unlikely to appear uniform to a viewer. For example the colour palette below shows a sequence of eight colours from almost white (247, 251, 255) to dark blue (8, 69, 148). The colours in between are calculated by taking 7 even steps from the almost white colour to the dark blue colour in the RGB space. These colouts are (213, 225, 240), (179, 199, 225), (145, 173, 210), (111, 147, 195), (77, 121, 180), and (43, 95, 165). In this palette the step from colour 1 to colour 2 is obvious, but colours 5 and 6 look almost identical.