5 Color Illusions and Why They Work

National Geographic Channel
National Geographic Channel

Think colors are objective facts? Think again! Color is more subjective than you might expect—it’s really all in your head. These illusions show you how.

1. Checkerboard Illusion

In this illusion, both block A and B are the same color.

Don’t believe it? Check this out.

It’s all because of color constancy, which helps the brain recognize objects regardless of the amount of light being reflected. Cone cells in our eyes help us see color. As these cones register different wavelengths of light, special neurons in the visual cortex try to make sense of the cone activity. Seeing that Square B is under a shadow, your brain assumes that the square must be even lighter than it really is.

2. Chubb Illusion

Another example of color constancy: the left inner box appears darker than the box on the right—although they’re the same color. Both squares reflect the same amount of light into your eyes, but they still appear different because of the context.

3. Scintillating Grid Illusion

This one is pretty trippy. Dark dots rapidly appear and disappear at the intersections. However, if you stare at one intersection, the crossroad remains white.

Scientists are still trying to put a finger on this one. One theory, called lateral inhibition theory, suggests that several photoreceptors in the eye send information to a retinal ganglion cell in the brain. As your brain interprets these signals, the most active brain cells inhibit and reduce the activity in neighboring cells, making them less excited. This creates an unequal black-white contrast.

4. The Cornsweet illusion

Lateral inhibition strikes again! Both panels are the same color. Just cover the fold with your finger to see it.

5. The Bezold Effect

Wilhelm von Bezold discovered that a color may appear darker depending on its context. In this picture, there’s only one shade of red, although the right side appears darker.

Scientists are still puzzled by this one. Some think lateral inhibition is to blame, although many disagree.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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10 of the Best True Crime Documentaries You Can Stream Right Now

A still from Frank Serpico (2017).
A still from Frank Serpico (2017).
IFC Films

Is the true crime genre going anywhere? Probably not. Since Errol Morris’s The Thin Blue Line premiered in 1988 and helped free an innocent man accused of murder, filmmakers and viewers have developed a bottomless appetite for movies based on true stories that shed light on some of the darker sides of the human condition. Check out some of the best true crime documentaries you can stream right now on Netflix, Amazon Prime, Hulu, and other platforms.

1. I Love You, Now Die (2019)

Teenagers in love Michelle Carter and Conrad Roy nourished their long-distance relationship via text messaging. But as Conrad’s moods grew darker, Michelle believed the best way to help her boyfriend would be to encourage him to take his own life. That dynamic sets the stage for a dramatic trial in Massachusetts that asks whether it's possible to be responsible for taking someone’s life via text.

Find It: HBO

2. Frank Serpico (2017)

An honest cop among thieves in late 1960s and early 1970s New York, Frank Serpico helped bring down corrupt officers and inspired the 1973 film Serpico starring Al Pacino. This film goes inside the mind of the man who made sure justice was being served—even at the risk of his own life.

Find it: Hulu

3. Dead Man's Line (2017)

In July 1977, a man named Tony Kiritsis phoned police in Indianapolis and told them he was holding a hostage named Richard Hall at gunpoint. But this was no typical crime: Kiritsis had strapped his shotgun to Hall's neck with a dead man's switch that would set off the trigger if cops shot and killed him. When he marched Hall out on the street, cops were helpless to intervene, which set off an astonishing chain of events. For Kiritsis, this dramatic display was personal, vengeful, and meant to be a spectacle—the result of a vendetta against the Hall family. What follows is a twist-laden and arresting portrait of a man who believes he's doing the wrong thing for the right reasons.

Find It: Amazon Prime

4. Out of Thin Air (2017)

In 1974, two men in Iceland disappeared. A police investigation led to six men, who were all eventually sent to prison after confessing to murder. Decades later, new evidence casts doubt on their version of events—and whether they killed anyone at all.

Find It: Netflix

5. Long Shot (2017)

Though it’s more of a short film than a feature, this examination of Juan Catalan’s fight to be recognized as innocent of committing murder is notable for his attorney’s methodology: Catalan couldn’t have done it because he was at a baseball game. How they go about proving that turns into one of the biggest left-field twists you’re ever likely to see.

Find It: Netflix

6. Killing for Love (2016)

When married couple Derek and Nancy Haysom are found dead in their Virginia home in 1985, suspicion falls on their daughter, Elizabeth, and Elizabeth’s boyfriend, Jens Söring. Was Jens a co-conspirator, or just a pawn in Elizabeth’s game? Watch and find out.

Find It: Hulu

7. Amanda Knox (2016)

College student Amanda Knox grabbed headlines in 2007 and beyond when her roommate, Meredith Kercher, was found dead in the apartment the two shared in Italy. What follows is a grueling path through an often-impenetrable Italian justice system.

Find It: Netflix

8. Dream/Killer (2015)

Bill Ferguson lived every parent's worst nightmare: In 2005, his son Ryan was sentenced to 40 years in prison for murder. But the elder Ferguson is convinced Ryan is innocent, setting off an unlikely chain of events that will test the foundation of the judicial system in America.

Find It: Netflix

9. Soaked in Bleach (2015)

The suicide of Kurt Cobain in 1994 was eulogized as a rock star tragedy. Soaked in Bleach ponders whether there was more to Cobain's life—and death—than was originally reported.

Find It: Amazon Prime

10. Without Charity (2013)

In 2000, police discovered a trio of construction workers who had been murdered at an expensive home in Indiana. As police dig deeper, they discover the puzzling presence of Charity Payne, a woman who might have helped a group of robbers to break in and commit the murders.

Find It: Amazon Prime