> It has to do with edge detection. The signals from receptors in the eye are used not only to detect color, but also to detect edges. In fact since color is detected largely by differences of spectral response from nearby receptors, the edges are important because that's where the strongest difference lies. The color of a region, especially a small one, is largely determined at the edges.
Aha! So that is why I have the hardest time with line charts even when I distinguish the colors in the legend just fine!
Aha! So that is why I have the hardest time with line charts even when I distinguish the colors in the legend just fine!