Raw Visual Input

Before your brain groups anything into patterns, before it even decides what matters, your eyes have already run their own first pass: light lands on the retina, gets converted into signals for contrast, edges and colour, and gets routed toward the visual cortex — all before a single conscious thought happens. Two things about that first pass matter enormously for anyone building a chart. First, colour is a fragile signal on its own: poor contrast, or leaning on hue with nothing else backing it up, can distort what a reader sees before their brain even starts interpreting it. Second, not every visual system receives that signal the same way — roughly 1 in 12 men and 1 in 200 women have some form of colour vision deficiency, and plain low contrast is a problem for a great many more readers than that. The tabs below let you see effects like these live.

Pick a tab below to try one.

What this teaches: Run a colour palette through colour-blindness simulations and compare hue-only contrast with hue plus lightness. It teaches early visual processing, colour-vision deficiency, lightness contrast and pattern glare.