The latest buzzy optical illusion is here, and we have to admit, it’s pretty cool. Created by Irish artist Matt Loughrey, this series of inverted black and white images will trick your mind into perceiving them as color.
Here’s what you do: Stare at the white dot on the nose of each subject for 20 seconds, preferably in a room with dim lighting. Then look away to a blank wall; all the while, allow yourself to blink normally. You should see a colorized ghost image.
As Loughrey explained to IFLScience, the images came about when he was playing with a computer-based editing technique, called SMTM, developed by himself and his partner, Sarah McWalter, for their work as professional historical photo colorists.
“The image is accurately colorized using SMTM, which takes hours in some cases. It is then inverted and offset slightly. This helps the visual area of the brain accurately realize the inversion, thus producing a working 'afterimage.'” Loughrey said that the laborious SMTM process, done entirely by hand, has revolutionized the results of their colorization work.
“It essentially paved the way to creating something that is beyond 90 percent accurate without having to reference,” he told us. “It actually lifts details in historical imagery that is hidden in monochrome.”
“Sometime ago I stumbled upon the afterimage effect and said to myself this may apply to the colorization work, in that it would further the interactive nature of the work. We discussed it and set about realizing the idea.”
Here's how it works, according to Loughrey.
“When you focus on a picture, the cone cells (used for color) in our eyes become over-stimulated. After a short period of time, these cone cells are only sending a weak signal to your brain telling you what color you're looking at. This in turn makes the color muted and when you move your eyes to a blank space like an indoor wall or ceiling, your brain will compensate for that lack of information. This means when you look back at the image you will see it in color.”
Ophthalmologist Ajay Kuriyan, a retina specialist (the part of the eye that contains the rod and cone cells) at the University of Rochester Medical Center, confirms this to be true.
"If you stare at a color for some time, the cone cells responding to that color become refractory for a short period of time so the other color cone cells become stimulated. This is the principle that drives the after image," he told IFLScience, noting that more details on the phenomenon can be found here.
To view more of Loughrey and McWalter’s incredible work – which has been featured in many exhibits and publications, including National Geographic – check out the My Colorful Past Instagram.