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.

The new blue-yellow color scale is labelled CVD-JetNuñez 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 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

Buy it: Amazon

2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

Amazon

Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

Buy them: Amazon, Amazon

3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

Buy it: Amazon

4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

Amazon

The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

Buy it: Amazon

5. National Geographic Adventure Edition Road Atlas; $19

Amazon

Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

Buy it: Amazon

6. Adventure Medical Kits Hiker First-Aid Kit; $25

Amazon

This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

Buy it: Amazon

7. Hiker Hunger Ultralight Trekking Poles; $70

Amazon

Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

Buy it: Amazon

8. Leatherman Signal Camping Multitool; $120

Amazon

What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

Buy it: Amazon

9. RAVPower Power Bank; $24

Amazon

Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

Buy it: Amazon

10. Pack of Four Indestructible Field Books; $14

Amazon

Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

Buy it: Amazon

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China Is Now Home to What May Be the World’s Most Stunning Bookstore

The best place to get lost.
The best place to get lost.
Shao Feng/X+Living

Anywhere with books for sale is automatically a lovely place to be, but this new bookstore in southwest China just upped the ante with its jaw-dropping display of shelves.

The shop, located in Dujiangyan City, Sichuan, was designed by Li Xiang and her architectural firm X+Living. As Li mentioned on Instagram, she drew inspiration from Dujiangyan’s ancient irrigation system, which uses the rivers running in and around the city. You can definitely see its influence on her work; the towering arches and winding staircases evoke images of flowing water, and the mirrored ceiling makes the room seem infinite. ArchDaily points out that the curved display tables on the black tiled floor even look like boats in deep, placid water. Taking in the entire scene elicits a similar sense of awe that you might feel when observing a natural landscape.


View this post on Instagram

A post shared by Li Xiang | X+LIVING (@xlivingart) on

Then, there are the books themselves. While shelves stretch up to the ceiling (and seemingly beyond, thanks to those mirrors), visitors don’t have to worry about certain volumes being much too far to reach. The highest “shelves” are actually just wallpaper printed to look like bookshelves. According to designboom, the store also houses a children’s reading area, complete with green bamboo bookshelves, pictures of pandas, and bright-colored cushions.

It’s not the first time X+Living has created a space for book lovers. The Dujiangyan shop is the latest in the firm’s Zhonghuge series of bookstores around China, including locations in Beijing, Ningbo, Guiyang, and Chongqing. There are certain recurring design elements—like mirrored ceilings, curved shelves, and archways—but each has its own distinct style.

While you’re waiting for a chance to explore one of Li Xiang’s magical buildings, find out which bookstore is your state’s best one here.

[h/t designboom]