OI 1

There’s a pretty standard progression that most people go through when they come across a optical illusion. Once the effect is revealed, you’re supposed to have a moment of disbelief, which gives way to wonder at the mysterious way our senses work, and a deeper understanding of and appreciation for how the complex human neurological system comes together.

Or, if you’re the stubborn type, you never get past the disbelief stage. If that describes your usual reaction, today you’re in luck, because it turns out there are actually two twists to this image making the round online in Japan, and possibly only one of them is intentional.

We first came across the image on Japanese website Agohige Kaizokudan. Perhaps inspired by the recent blue/white/black/gold dress brouhaha, it’s another attempt to show how your eyes perceive color.

The illusion consists of an image of two blocks (or dislodged keyboard keys, or perhaps delicious marshmallows) stacked one on top of the other.

OI 1

Now for the illusion. According to Agohige Kaizokudan, if you cover up the section marked below in pink, the two blocks will “appear to be the same color.”

OI 2

In case you’re right in the middle of eating a bag of Cheetos and don’t want to get cheese dust all over your monitor, allow us to black out that section for you.

OI 3

Wow, crazy, huh? They totally look like they’re the same color now! So is this another example of your eyes needing to find a contrast in order to differentiate between two different shades, like the video we talked about earlier this month where placing a pencil on the border between different hues of blue caused them to all look the same?

Well, not exactly. Actually, not at all.

Let’s take one more look at the image with the dividing line between the blocks blacked out.

OI 3

Sure, Blocks A and B definitely look like they’re the same color now. But next, let’s grab a sample from each.

OI 4

If the illusion is working like we’re being led to believe, the only reason the two sections marked in yellow look to be the same color is because that black box is blocking the transition our eyes need to realize the difference. So to reestablish the transition, let’s chop out those two yellow boxes…

OI 5

…zoom in a bit…

OI 6

…and finally, isolate just the two boxes.

OI 7

Okay, now all we have to do is overlap one with the other, and we’ll be able to see the difference, right? So, shave off the yellow borders…

OI 8

…and now it’s time so slap them together!

OI 9

…huh? Unless we’ve suddenly gone colorblind, the samples we took from Blocks A and B are exactly the same color.

In the end, covering up the border between the two blocks makes them “appear” to be the same color in the same way that Tokyo “appears” to be in Japan. At this stage…

OI 3

…Blocks A and B don’t “appear” to be the same color, they are the same color.

In the end, the purported “Gotcha!” moment doesn’t hold water, because it’s not really an optical illusion playing tricks on our eyes. On the other hand, the image inadvertently does a good job illustrating how we immediately process the information shading and perspective provide in 2-D artwork simulating 3-D objects.

OI 1

Because of the direction of the lines and coloring in the above image, we quickly interpret Block A as being a single shade of gray and largely in the light, and Block B as a single shade of white and mainly in the shadow. So when something makes us think parts of a gray and white block are the same color, it’s easy to see how we could jump to the conclusion of, “Whoa, it’s an optical illusion!”

Except, not a single one of these pictures is actually showing any light or shadow. They’re all digitally created, and while the effects may be realistic, they’re not actually real. There’s no way to put a block that’s both completely white and entirely virtual into an actual shadow. You just make the color darker to simulate the effect. Likewise, you can’t hit a digital gray block with a spotlight, but you can lighten the shade where light would strike a physical block.

And when you make white darker and gray lighter, it’s only natural that they both end up as an identical light gray.

▼ Drawing samples from the part you’re supposed to cover up, meanwhile shows an undeniable difference.

OI 10

So rest easy knowing that, at least this time, you can trust your eyes.

Source: Agohige Kaizokudan
Top image: Agohige Kaizokudan
Insert images: Agohige Kaizokudan (edited by RocketNews24)