How Does the Magic Yellow First-Down Line Work?

Sportvision
Sportvision

If you attend a Super Bowl party on Sunday, you’ll probably hear at least one casual football viewer ask, “How do they get that yellow first-down line on the field?” While “magic” is a fine answer in its own right, the real explanation is a bit more technologically intense. Let’s have a look at the background and mechanics behind every football fan’s shining beacon: the yellow first-down line.

According to Allen St. John’s 2009 book The Billion Dollar Game: Behind the Scenes of the Greatest Day in American Sport - Super Bowl Sunday, the first-down line actually emerged from the ashes of one of sports broadcasting’s bigger debacles: the FoxTrax system for hockey, which was designed by a company called Sportvision. FoxTrax—which hockey fans no doubt remember as the much-maligned “technopuck” that debuted in 1996—employed a system of cameras and sensors around a hockey rink to place a little blue halo around the puck.

FoxTrax wasn't a great fit for NHL broadcasts: Hockey purists hated the intrusion into their game, and casual fans didn’t flock to hockey just because the puck was suddenly easier to follow. However, the system inspired producers to think of new ways to insert computerized images into live sports broadcasts.

The idea of using a line to mark the first down in football was a natural extension, and Sportvision debuted its 1st and Ten system during ESPN’s broadcast of a Bengals-Ravens tilt on September 27, 1998. A couple of months later, rival company Princeton Video Image unveiled its Yellow Down Line system during a Steelers-Lions broadcast on CBS. (Sportvision is still kicking, and ESPN acquired all of PVI’s intellectual property in December 2010.)

BUT HOW DOES IT WORK?

It takes lots of computers, sensors, and smart technicians to make this little yellow line happen. Long before the game begins, technicians make a digital 3D model of the field, including all of the yard lines. While a football field may look flat to the naked eye, it’s actually subtly curved with a crown in the middle to help rainwater flow away. Each field has its own unique contours, so before the season begins, broadcasters need to get a 3D model of each stadium’s field.

These models of the field help sidestep the rest of the technological challenges inherent to putting a line on the field. On game day, each camera used in the broadcast contains sensors that record its location, tilt, pan, and zoom and transmit this data to the network’s graphics truck in the stadium’s parking lot. These readings allow the computers in the truck to process exactly where each camera is within the 3D model and the perspective of each camera. (According to How Stuff Works, the computers recalculate the perspective 30 times per second as the camera moves.)

After they get their hands on all of this information, the folks in the graphics truck know where to put the first-down line, but that’s only part of the task. When you watch a football game on television, you’ll notice that the first-down line appears to actually be painted on the field; if a player or official crosses the line, he doesn’t turn yellow. Instead, it looks like the player’s cleat is positioned on top of an actual painted line. This effect is fairly straightforward, but it’s difficult to achieve.

To integrate the line onto the field of play, the technicians and their computers put together two separate color palettes before each game. One palette contains the colors—usually greens and browns—that naturally occur on the field’s turf. These colors will automatically be converted into yellow when the line is drawn on to the field.

All of the other colors that could show up on the field—things like uniforms, shoes, footballs, and penalty flags—go into a separate palette. Colors that appear on this second palette are never converted into yellow when the first-down line is drawn. Thus, if a player’s foot is situated “on” the line, everything around his cleat will turn yellow, but the cleat itself will remain black. According to How Stuff Works, this drawing/colorizing process refreshes 60 times per second.

All this technology—and the people needed to run it—wasn’t cheap at first. It could cost broadcasters anywhere from $25,000 to $30,000 per game to put the yellow line on the field. Sportvision had to deploy a truck and a four-man crew with five racks of equipment. The cost has come down since then, and the process is now less labor-intensive. One technician using one or two computers can run the system, according to Sportvision, and some games can even be done without anyone actually at the venue.

Now you can explain it to everyone at your Super Bowl party during one of the less-exciting $5 million commercials.

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This post originally appeared in 2011.

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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Who Were the Actual Brooks Brothers?

Phillip Pessar, Flickr // CC BY 2.0
Phillip Pessar, Flickr // CC BY 2.0

Brooks Brothers has been a mainstay of American formal wear for more than 200 years. The company’s suits have been worn by 40 U.S. presidents. They have supplied uniforms to the American armed forces and suits to regular people for their most important life events: going to the prom, attending their first job interview, getting married.

But in July 2020, the firm filed for bankruptcy, likely a victim of the working-from-home trend and the move towards more casual clothing. The Brooks Brothers’s name has been woven into the fabric of American fashion, yet a certain mystery surrounds the people behind the business. Who were the original Brooks Brothers, anyway?

The firm that would go on to be known as Brooks Brothers was established on April 7, 1818, by 45-year-old Henry Sands Brooks and his younger brother, David, as H & D. H. Brooks and Co. Before setting up the store, Henry Sands Brooks had been a provisioner for traders and seafarers, and likely did brisk business in New York City’s seaport. Their shop was situated on the corner of Catherine and Cherry streets in Lower Manhattan, a major shopping district that supported a number of clothing stores. It was said Brooks was something of a dandy with an eye for fashion.

Brooks Brothers ran a full-page ad celebrating its centenary in 1918.New York Evening Post // Public Domain

Henry Sands Brooks died in 1833, and the store passed to his eldest son, Henry Jr. When he died in 1850, Brooks Sr.’s four younger sons Daniel, John, Elisha, and Edward inherited the firm and renamed it Brooks Brothers. At this point, the store began to stand out from the crowd. The brothers adopted their familiar logo of a sheep suspended by a ribbon representing the Golden Fleece. This ancient symbol hearkened back to the Greek legend of Jason and the Argonauts, and was used by tailors and wool merchants across Europe as a sign of quality. By embracing this symbol, the brothers were announcing the caliber of their goods and aligning themselves with the prestige of European fashion.

While building a brand on traditional quality, the brothers also saw an opportunity to modernize. Brooks Brothers began specializing in ready-to-wear suits—an innovation that made “gentlemen’s clothing” accessible and affordable to ordinary Americans. An advertisement in New York’s Evening Post in June 1850 stated that Brooks Brothers ‘have on hand a large stock of ready-made clothing, suited to the tastes and wants of purchasers.’ Brooks Brothers also capitalized on the California Gold Rush by selling their ready-made suits to gold-seekers who didn’t have time to wait for a tailor to construct bespoke suits.

Business boomed in the years leading up to the Civil War, a time when the company benefited from slavery. Much of the cotton used by Brooks Brothers was picked by enslaved laborers in the South. The company also manufactured the types of uniforms worn by enslaved people forced to work as house servants.

Perhaps as a result of their experience making such clothing, Brooks Brothers was given a large contract by the Union government at the start of the Civil War to provide tens of thousands of uniforms for enlisted soldiers. A scandal blew up when the garments were delivered: it was obvious that the uniforms were of low quality, missing buttons or buttonholes, and made from cheap scraps of cloth glued instead of sewn together. When the outfits were exposed to wind and rain, they fell apart. In the rush to manufacture them for the war effort, Brooks Brothers had, in fact, substituted cheap and flimsy material instead of the usual grade of cloth—they were allowed to, according to the provisions written into their contract.

The New York state legislature launched an investigation, accusing the company of profiteering. When asked how much money the company had made by downgrading the cloth, Elisha Brooks prevaricated. “I think that I cannot ascertain the difference without spending more time than I can now devote to that purpose,” Brooks told lawmakers. Ultimately, Brooks Brothers agreed to replace 2350 of the substandard uniforms at a cost of $45,000.

An illustration of looters throwing trousers and other garments out of the Brooks Brothers store during New York City's draft riots appeared on the front page of Frank Leslie's Illustrated Newspaper on August 1, 1863.Frank Leslie's Illustrated Newspaper, 19th Century American Newspapers, Gale Primary Sources // Public Domain

The company’s association with outfitting the Union Army got them into trouble again in July 1863. The casualties among members of New York regiments were increasing as the war showed no signs of resolution. In New York City, working class people protested against the draft, and the protests quickly turned into a riot of racist violence and looting. Brooks Brothers’s Cherry Street store was one of the establishments it targeted. Harper’s Weekly reported that “a large number of marauders paid a visit to the extensive clothing-store of Messrs. Brooks Brothers … there they helped themselves to such articles as they wanted, after which they might be seen dispersing in all directions, laden with their ill-gotten booty.”

Brooks Brothers’s reputation didn’t suffer for long, however. At his second presidential inauguration in March 1865, Abraham Lincoln wore a greatcoat made by the company. It featured an eagle embroidered into its lining with the motto “One Country, One Destiny.” Lincoln was wearing the same coat when, just two weeks later, he was assassinated at Ford’s Theatre in Washington, D.C. After his death, Mary Todd Lincoln gave the coat to Alphonse Donn, a doorman at the White House, who kept it for the rest of his life. Donn’s family eventually sold the coat to the United States Capitol Historical Society, and it is now in the Ford’s Theatre museum's collection.

Brooks Brothers continued to grow and expand. The company introduced enduring fashions such as the button-down polo shirt in 1896, the sack suit in 1901, and their own version of a British regimental tie, the striped rep tie, in 1902.

For more than 200 years, the company has outfitted presidents, Wall Street traders, and businesspeople, becoming an iconic American brand with worldwide appeal. But today, their future may be less certain.