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Rob van Lier, PhD
Associate Professor


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A few illusions

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The case of the Black & Blue dress, or was it Gold &White..? On February 27, 2015, the internet community seemed to be divided into two camps: Those who saw a Black & Blue dress (in a tweeted picture that went viral) versus those who saw a Gold & White dress. The following animation may help to understand why an otherwise black and blue dress may also appear gold and white. Normally we see objects having constant colors, also under different lighting conditions (e.g., lighting conditions in bright daylight are quite different from lighting conditions inside a building). In the original image there is too little information to judge the situation. For example, our visual system may assume that the dress color inside the frame (see animation below) is the result of a picture taken in bluish daylight. Then, filtering out bluish colors (because they would not belong to the dress itself) further enhances the gold-and-white percept. Similarly, accounting for yellowish lighting effects would more likely result in a black-and-blue percept.. The animation aims to show that adding more context may turn an initial gold-and-white percept into a black-and-bluish one. Well, the coin can fall to both sides. And yes, colors are a mental construct..  

The dress