What Color Is a Tennis Ball? The Answer Is Complicated—And Depends on Who You Ask

iStock.com/jujeecmu
iStock.com/jujeecmu

While there’s always some subjectivity in visual perception, some colors are supposed to be constant. Oranges are always orange. Fire trucks are always red. Tennis balls are always yellow.

Or maybe they’re always green.

In The Atlantic, Marina Koren explored the controversial debate over where the ubiquitous felt ball seen on courts or shooting out of serving machines falls on the color spectrum. After discovering that her colleagues perceived the ball different ways—either yellow or green—she attempted to understand why and if there was a definitive answer lurking in those ball cans.

By rule of tennis law—specifically, the International Tennis Federation, or ITF—a tennis ball should be yellow in color. The edict was handed down in 1972, after television viewers had trouble following the movement of white balls. Manufacturers like Gamma Sports also identify their product as yellow—in Gamma’s case, optic yellow.

So why do some people perceive the balls as green? For one thing, a yellow hue presented by itself can be hard for some people to describe. Yellow is easy to identify when contrasted with other colors—think paint swatches—but harder for people to articulate when there’s nothing to compare it to. Second, people tend to make color corrections based on lighting conditions. Some may discount warm colors like gold or cool colors like blue, changing how they perceive and interpret the color spectrum. If they discount cool colors, the ball might appear to be yellow. If they discount warm colors, green.

It’s possible that people who are active in the evenings under artificial light are more likely to discount warm colors, while people active in the daytime and under natural light would discard cool colors, further altering their perceptions.

Objectively, a tennis ball is yellow. But whether it appears that way to you depends on how you see the world.

[h/t The Atlantic]

Kodak’s New Cameras Don't Just Take Photos—They Also Print Them

Your Instagram account wishes it had this clout.
Your Instagram account wishes it had this clout.
Kodak

Snapping a photo and immediately sharing it on social media is definitely convenient, but there’s still something so satisfying about having the printed photo—like you’re actually holding the memory in your hands. Kodak’s new STEP cameras now offer the best of both worlds.

As its name implies, the Kodak STEP Instant Print Digital Camera, available for $70 on Amazon, lets you take a picture and print it out on that very same device. Not only do you get to skip the irksome process of uploading photos to your computer and printing them on your bulky, non-portable printer (or worse yet, having to wait for your local pharmacy to print them for you), but you never need to bother with ink cartridges or toner, either. The Kodak STEP comes with special 2-inch-by-3-inch printing paper inlaid with color crystals that bring your image to life. There’s also an adhesive layer on the back, so you can easily stick your photos to laptop covers, scrapbooks, or whatever else could use a little adornment.

There's a 10-second self-timer, so you don't have to ask strangers to take your group photos.Kodak

For those of you who want to give your photos some added flair, you might like the Kodak STEP Touch, available for $130 from Amazon. It’s similar to the regular Kodak STEP, but the LCD touch screen allows you to edit your photos before you print them; you can also shoot short videos and even share your content straight to social media.

If you want to print photos from your smartphone gallery, there's the Kodak STEP Instant Mobile Photo Printer. This portable $80 printer connects to any iOS or Android device with Bluetooth capabilities and can print whatever photos you send to it.

The Kodak STEP Instant Mobile Photo Printer connects to an app that allows you to add filters and other effects to your photos. Kodak

All three Kodak STEP devices come with some of that magical printer paper, but you can order additional refills, too—a 20-sheet set costs $8 on Amazon.

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10 Fast Facts About Wilma Rudolph

Wilma Rudolph breaks the tape as she wins the Olympic 4 x 100 relay in 1960.
Wilma Rudolph breaks the tape as she wins the Olympic 4 x 100 relay in 1960.
Robert Riger/Getty Images

Wilma Rudolph made history as a Black female athlete at the 1960 Summer Olympics in Rome, Italy. The 20-year-old Tennessee State University sprinter was the first American woman to win three gold medals at one Olympics. Rudolph’s heroics in the 100-meter, 200-meter, and 4 x 100-meter events only lasted seconds, but her legend persists decades later, despite her untimely 1994 death from cancer at age 54. Here are some facts about this U.S. Olympic Hall of Fame member.

1. Wilma Rudolph faced poverty and polio as a child.

When Rudolph was born prematurely on June 23, 1940, in Clarksville, Tennessee, she weighed just 4.5 pounds. Olympic dreams seemed impossible for Rudolph, whose impoverished family included 21 other siblings. Among other maladies, she had measles, mumps, and pneumonia by age 4. Most devastatingly, polio twisted her left leg, and she wore leg braces until she was 9.

2. Wilma Rudolph originally wanted to play basketball.

The Tennessee Tigerbelles. From left to right: Martha Hudson, Lucinda Williams, Wilma Rudolph, and Barbara Jones.Central Press/Getty Images

At Clarksville’s Burt High School, Rudolph flourished on the basketball court. Nearly 6 feet tall, she studied the game, and ran track to keep in shape. However, while competing in the state basketball championship in Nashville, the 14-year-old speedster met a referee named Ed Temple, who doubled as the acclaimed coach of the Tennessee State Tigerbelles track team. Temple, who would coach at the 1960 and 1964 Olympics, recruited Rudolph.

3. Wilma Rudolph made her Olympic debut as a teenager.

Rudolph hit the limelight at 16, earning a bronze medal in the 4 x 100-meter relay at the 1956 Summer Olympics in Melbourne, Australia. But that didn’t compare to the media hype when she won three gold medals in 1960. French journalists called her “The Black Pearl,” the Italian press hailed “The Black Gazelle,” and in America, Rudolph was “The Tornado.”

4. After her gold medals, Wilma Rudolph insisted on a racially integrated homecoming.

Tennessee governor Buford Ellington, who supported racial segregation, intended to oversee the Clarksville celebrations when Rudolph returned from Rome. However, she refused to attend her parade or victory banquet unless both were open to Black and white people. Rudolph got her wish, resulting in the first integrated events in the city’s history.

5. Muhammad Ali had a crush on Wilma Rudolph.

Ali—known as Cassius Clay when he won the 1960 Olympic light heavyweight boxing title—befriended Rudolph in Rome. That fall, the 18-year-old boxer invited Rudolph to his native Louisville, Kentucky. He drove her around in a pink Cadillac convertible.

6. John F. Kennedy literally fell over when he invited Wilma Rudolph to the White House.

President Kennedy, Wilma Rudolph, Rudolph’s mother Blanche Rudolph, and Vice President Johnson in the Oval Office.Abbie Rowe/White House Photographs/John F. Kennedy Presidential Library and Museum // Public Domain

In 1961, Rudolph met JFK in the Oval Office. After getting some photos taken together, the President attempted to sit down in his rocking chair and tumbled to the floor. Kennedy quipped: “It’s not every day that I get to meet an Olympic champion.” They chatted for about 30 minutes.

7. Wilma Rudolph held three world records when she retired.

Rudolph chose to go out on top and retired in 1962 at just 22 years old. Her 100-meter (11.2 seconds), 200-meter (22.9 seconds), and 4 x 100-meter relay (44.3 seconds) world records all lasted several years.

8. Wilma Rudolph visited West African countries as a goodwill ambassador.

The U.S. State Department sent Rudolph to the 1963 Friendship Games in Dakar, Senegal. According to Penn State professor Amira Rose Davis, while there, Rudolph independently met with future Ghanaian president Kwame Nkrumah’s Young Pioneers, a nationalist youth movement. She visited Mali, Guinea, and the Republic of Upper Volta (now Burkina Faso) as well.

9. Denzel Washington made his TV debut in a movie about Wilma Rudolph.

Before his Oscar-winning performances in Glory (1989) and Training Day (2001), a 22-year-old Denzel Washington portrayed Robert Eldridge, Rudolph’s second husband, in Wilma (1977). The film also starred Cicely Tyson as Rudolph’s mother Blanche.

10. Schools, stamps, and statues commemorate Wilma Rudolph’s legacy.

Berlin, Germany, has a high school named after Rudolph. The U.S. Postal Service issued a stamp celebrating her in 2004. Clarksville features a bronze statue by the Cumberland River, the 1000-capacity Wilma Rudolph Event Center, and Wilma Rudolph Boulevard. In Tennessee, June 23 is Wilma Rudolph Day.