The world that surrounds us is made from a combination of three main colours: red, yellow and blue.

Known as the primary colours, it's the first thing we learn in primary school art class. In illusions, however, our concept of colours becomes warped and fails us. The only question is how do we fix it?

 

Take the infamous colour-changing dress of 2015. This dress became an internet sensation due to its ambiguity of colour with the major question being “Is the dress black and blue or white and gold?” 

The dress, despite causing many online debates, is actually black and blue. Nevertheless this debate raises an important question about colours. Why do we see different colours in the same image?

 

Let's begin with colour theory. Colour theory is a set of guidelines that artists use when mixing colours within the spectrum. With the intention of provoking different psychological responses, colours are used to either complement or contrast one another [1]. We see this through the infamous dress - with black and blue complimenting each, then gold and white. Our highly subjective perception allows us to see visually appealing combinations of colours juxtaposed to contrasting combinations. 

 

However, what we also need to consider are the light sources being used. Ranging from natural light to blue light and other artificial lighting, the light that we are exposed to can alter our perspective of colour. On our devices, we see colours through a series of red, green, and blue pixels that combine to make new colours for every image that we see [2]. Similarly, the frequent manipulation of our devices’ brightness also contributes to different colours being shown on the screens. These are the primary reasons why the famous dress was perceived so differently by everyone: each device shows a different version of the same colour depending on its display settings, which affects how many red, green and blue pixels there are. 

 

In addition to the colour theory, another effect— the Bezold Effect—is at its peak with the infamous dress. The Bezold Effect is an optical illusion where a colour’s appearance is affected by the presence of colours that surround the object [3]. For this dress, it’s seen through the shadows that form on and around the bodice. With brighter surroundings, such as the sun or an overly brightened screen, the blue from the dress appears gold to the eye, while the black appears white. The dress reverts to its original colours when the screen is darkened or artificial light is used. 

 

Circling back to colour theory, the changes in colours aren’t randomly allocated: they are opposing colours of the colour wheel. The wheel is a visual illustration of colours arranged by their wavelength, used to display the relationship of primary colours to their corresponding secondary colours [4]. With blue contrasting a yellow or gold, the changes in lighting perfectly display the contrasting colours on the wheel. 

 

The fascinating nature of colours is not something we can fix. In the era of digital displays and evolving technologies, we can’t see things the “right” way because there is no notable “right” or “wrong” way to look at the world. The dress is just one of those illusions that changes depending on the context and surroundings that it’s placed in. You can manipulate these colours and force them to change by physically changing the brightness on a device. 

 

So out of curiosity, I decided to conduct a little experiment of my own through an Instagram poll to see what my friends thought of this dress. While only 37 people participated, it was still fun to see what would happen with the votes; however, I was surprised to see the results after 24 hours. I expected a majority to choose the “real” colour of the dress, since the dress has been around in the media for a while and the answer is also online, but people still had contrasting opinions about the dress. With only 54% of people seeing black and blue and 46% white and gold, I began questioning our vastly different perceptions. The answer always seemed obvious as the dress was always black and blue not white and gold but that didn’t mean that other people saw what I saw. 

 

My favourite response came from a friend who saw the dress as blue and gold and after that, my opinion changed. For me, the dress is now blue and with tints of gold and I can’t see it any other way. This truly goes to show that there’s more behind the dress than what meets the eye. When I first saw the image my brightness was at the lowest it could possibly be and now after looking at the image enough, it’s just blue and gold. 

 

The ambiguity of this image is what makes the dress the best example of a real-life illusion. Other colour combinations act the same way in different lighting, but what we see is completely dependent on our perceptions, and every now and then, it’s always fun to put up a debate.