Seeing Isn’t Believing: How Visual Illusions Distort Color Selection

Color selection interfaces, such as color palettes and pickers, are essential tools in digital design software. However, these interfaces can unintentionally introduce visual illusions, particularly when the surrounding area alters the perceived appearance of the selected color. This study investigates how such illusions, especially brightness effects, distort color perception and lead to mismatches between selected and applied colors. Through two experiments, we make four key contributions. First, we empirically demonstrate that brightness illusions systematically bias color selection depending on the luminance of the surrounding area. Second, we show that decreasing the display size of the selected color increases perceptual inaccuracies, highlighting the importance of visual emphasis in interface layout. Third, we examine the influence of chromatic backgrounds and identify specific hues and framing conditions that minimize inaccuracy. Finally, based on these findings, we offer practical design implications for improving the accuracy and intuitiveness of color selection interfaces. Our results underscore the need to account for perceptual mechanisms when designing tools that support precise visual tasks.