New Color Scale Makes Data Visualizations Easier for Colorblind People to Read

Mars topography visualized on a rainbow scale
Mars topography visualized on a rainbow scale
NASA/JPL/USGS

When designers want to visualize changes in data, like in a heat map or a topographical survey, they often reach for the rainbow. The rainbow color scale is almost the default for visualizing scientific and engineering data. And yet, putting all the colors of the rainbow into a single image isn’t a good idea. For one thing, as Scientific American reports, it makes visualizations impossible to read if you’re colorblind. And even if you can pick out every color in the image, that doesn’t mean you understand what going from red to violet means.

Now, researchers from the U.S. Department of Energy’s Pacific Northwest National Laboratory in Washington have developed an alternative to the rainbow color scale that will make data visualization and other images easier to decipher for people with color-vision deficiency and the general public. Using a mathematical model of how the brain perceives differences in color, they created a new color scale they call cividis, which shows data exclusively in shades of blue and yellow—the colors that someone with colorblindness would see while looking at a rainbow color scale.

A nanoscale image overlaid with four different color scales
The new blue-yellow color scale is labelled CVD-Jet
Nuñez et. al, PLOS ONE (2018)

They took traditional rainbow color maps and ran them through software that converted them to look closer to the blue-yellow scale that reflects what someone with the most common form of colorblindness sees. Then, the software adjusted the color and brightness of that image to look more consistent with how people interpret data. One of the problems with the rainbow scale is that people automatically see the brightest color as a peak, sometimes leading them to incorrect conclusions. Even though yellow is one of the middle colors in Roy G. Biv, it often jumps out at people as the most extreme color on the map, though red is the highest on the scale. In this color scale, the color does get brighter as the values go up, so you don't have to work as hard to interpret it.

In general, most people don’t intuitively know what order the colors of the rainbow should appear in at all. Red and violet are at opposite ends of the Roy G. Biv scale, but that’s not visually apparent. Narrowing the range down to two colors makes it easier for readers to pinpoint where on the scale a specific point is.

The two-color scale also makes changes in data look more gradual, whereas with a rainbow of colors, the difference between each color looks very stark. The ability to show a gradual progression can reflect more nuance.

It’s not just a matter of aesthetics. An eye-catching, complex rainbow visualization can lead scientists to misinterpret their own data, while an easier-to-read scale makes it easier for them to pick out patterns. In one 2011 study cited by Scientific American [PDF], scientists at Harvard found that doctors were faster and better at spotting signs of heart disease while looking at 2D images of arteries on a color scale that just used black and red than while looking at a 3D rainbow visualization.

Cividis has already been added to the color-scale libraries of some image-processing software, and its creators hope to convince more scientists and designers to use it in the future.

[h/t Scientific American]

10 Wireless Chargers Designed to Make Life Easier

La Lucia/Moshi
La Lucia/Moshi

While our smart devices and gadgets are necessary in our everyday life, the worst part is the clumsy collection of cords and chargers that go along with them. Thankfully, there are more streamlined ways to keep your phone, AirPods, Apple Watch, and other electronics powered-up. Check out these 10 wireless chargers that are designed to make your life convenient and connected.

1. Otto Q Wireless Fast Charging Pad; $40

Otto Q Wireless Fast Charging Pad
Moshi

Touted as one of the world's fastest chargers, this wireless model from Moshi is ideal for anyone looking to power-up their phone or AirPods in a hurry. It sports a soft, cushioned design and features a proprietary Q-coil module that allows it to charge through a case as thick as 5mm.

Buy it: Mental Floss Shop

2. Gotek Wireless Charging Music Station; $57

Gotek Wireless Charging Music Station
Rego Tech

Consolidate your bedside table with this clock, Bluetooth 5.0 speaker, and wireless charger, all in one. It comes with a built-in radio and glossy LED display with three levels of brightness to suit your style.

Buy it: Mental Floss Shop

3. BentoStack PowerHub 5000; $100 (37 percent off)

BentoStack PowerHub 5000
Function101

This compact Apple accessory organizer will wirelessly charge, port, and store your device accessories in one compact hub. It stacks to look neat and keep you from losing another small piece of equipment.

Buy it: Mental Floss Shop

4. Porto Q 5K Portable Battery with Built-in Wireless Charger; $85

Porto Q 5K Portable Battery with Built-in Wireless Charger
Moshi

This wireless charger doubles as a portable battery, so when your charge dies, the backup battery will double your device’s life. Your friends will love being able to borrow a charge, too, with the easy, non-slip hook-up.

Buy it: Mental Floss Shop

5. 4-in-1 Versatile Wireless Charger; $41 (31 percent off)

4-in-1 Versatile Wireless Charger
La Lucia

Put all of those tangled cords to rest with this single, temperature-controlled charging stand that can work on four devices at once. It even has a built-in safeguard to protect against overcharging.

Buy it: Mental Floss Shop

6. GRAVITIS™ Wireless Car Charger; $20 (31 percent off)

GRAVITIS™ Wireless Car Charger
Origaudio

If you need to charge your phone while also using it as a GPS, this wireless device hooks right into the car’s air vent for safe visibility. Your device will be fully charged within two to three hours, making it perfect for road trips.

Buy it: Mental Floss Shop

7. Futura X Wireless 15W Fast Charging Pad; $35 (30 percent off)

Futura X Wireless 15W Fast Charging Pad
Bezalel

This incredibly thin, tiny charger is designed for anyone looking to declutter their desk or nightstand. Using a USB-C cord for a power source, this wireless charger features a built-in cooling system and is simple to set up—once plugged in, you just have to rest your phone on top to get it working.

Buy it: Mental Floss Shop

8. Apple Watch Wireless Charger Keychain; $20 (59 percent off)

Apple Watch Wireless Charger Keychain
Go Gadgets

This Apple Watch charger is all about convenience on the go. Simply attach the charger to your keys or backpack and wrap your Apple Watch around its magnetic center ring. The whole thing is small enough to be easily carried with you wherever you're traveling, whether you're commuting or out on a day trip.

Buy it: Mental Floss Shop

9. Wireless Charger with 30W Power Delivery & 18W Fast Charger Ports; $55 (38 percent off)

Wireless Charger from TechSmarter
TechSmarter

Fuel up to three devices at once, including a laptop, with this single unit. It can wirelessly charge or hook up to USB and USB-C to consolidate your charging station.

Buy it: Mental Floss Shop

10. FurniQi Bamboo Wireless Charging Side Table; $150 (24 percent off)

FurniQi Bamboo Wireless Charging Side Table
FoneSalesman

This bamboo table is actually a wireless charger—all you have to do is set your device down on the designated charging spot and you're good to go. Easy to construct and completely discreet, this is a novel way to charge your device while entertaining guests or just enjoying your morning coffee.

Buy it: Mental Floss Shop

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Key West Has Installed Permanent Rainbow Crosswalks

In Key West, rainbow crosswalks aren't just for Pride Month.
In Key West, rainbow crosswalks aren't just for Pride Month.
Maxvis/iStock via Getty Images

In 2015, Key West became the first place in Florida to install permanent rainbow crosswalks—a celebration of LGBTQ+ pride that reflected the city’s “One Human Family” motto. But a few years later, the city decided to repave its historic Duval Street, which required tearing up the four colorful paths at the intersection of Petronia Street.

The rainbow crosswalks finally returned this week—just in time for Pride Month—and they’re even more vibrant than before. The old ones were essentially regular white crosswalks with each empty space filled in with a different color, whereas the new paths feature long, colored stripes with a white stripe along the top and bottom edges.

According to NBC 6 South Florida, workers positioned the thermoplastic stripes on the street and attached them to the pavement below with heat from propane torches. Key West mayor Teri Johnson and other officials then commemorated the new landmarks, located in the heart of the city's entertainment district, with a ribbon-cutting ceremony. (The ribbon was also rainbow colored, and all participants wore masks to prevent the spread of coronavirus.)

“The rainbow crosswalks mean that everybody is welcome, everybody is equal, everybody is recognized, and that we do really abide by the ‘One Human Family’ spirit,” Johnson said.

Key West isn’t the only place with permanent rainbow paths; as LGBTQ Nation reports, you can find them in San Francisco, West Hollywood, Seattle, Philadelphia, Toronto, and other cities, too. And while the small island city has postponed its Pride events until November due to the pandemic, some of the world's biggest Pride parades and festivals are simply moving the party online: Here are 10 events to check out this month.

[h/t NBC 6 South Florida]