What can we learn from a dress with ambiguous colors?

Abstract

We performed objective spectroradiometric measurements on an LCD image of the recently famous Tumblr dress which is typically perceived by people as blue/black or white/gold. The average ± standard deviation of the CIELAB coordinates was as follows: For a set of 33 points in the areas considered as blue/white, L∗= 46 ± 6, C∗ab = 33 ± 6, and hab = 282 ± 3, and for a set of 36 points in the areas considered as black/gold, L∗= 29 ± 6; C∗ab = 10 ± 4; hab = 16 ± 34. Initially, this first set of values has low variability and corresponds to a blue color, whereas the second set of values has a very large hue-angle range, including points which can be considered as both gold and black colors. We also performed spectrophotometric measurements on an original model of this dress, and, assuming D65 illuminant and CIE 1931 colorimetric standard observer, the average results were L∗= 26, C∗ab = 39, and hab = 289, and L∗= 10, C∗ab = 1, and hab = 290 for the blue/white and black/gold points, respectively. We discuss the influence of different factors on the blue/black and white/gold perceptions of different people, including observers' variability in color-matching functions, Bezold-Brücke and Abney effects, background influence, and illumination assumptions. Although more research on the effect shown in this dress is needed, we think that from this example we can learn that objects do not have specific colors; that is, color is a human perception, and many times the answer of the human visual system is not simple and relies on assumptions of unknown, and variable, origin.