Adobe’s Kuler color app is a great tool for designers but is your display accurate enough for it?

Posted on June 13, 2013 by Jeff Yurek

Screenshot of Adobe’s Kuler app showing color extraction from a photo

Adobe recently released a new iPhone app called Kuler that let’s you extract colors from your surroundings using the phone’s camera. It’s a useful tool that allows designers to capture color inspiration wherever they find it and easily incorporate it into their work via color palettes.

The app also highlights a weakness in current display technology: no display on the market today can actually reproduce all the colors we see in the environment around us. So, even if the camera sensor can capture that color you love, you may not be seeing an accurate representation of it on your device.

The iPhone 5′s LCD display is designed to cover the sRGB/rec.709 color gamut standard used for HDTV broadcasts. And, it looks great but compared to the world we see around us, it’s just not quite as rich. If we plot the iPhone 5′s color gamut against the gamut of colors found in nature, the phone comes up short in important reds, greens and cyans:

Color gamut of the iPhone 5′s display compared to the gamut of colors found in nature. The iPhone 5 comes up short in red, green and cyan.

If DisplayWeek 2013 was any indication, color has once again become a hot topic in the display industry. Color gamuts are getting larger and it may not be long before we see a display that can match what our eye sees in nature. Over the course of the next year, we will start to see more wide color gamut-capable devices as OLED continues to expand marketshare and new technologies like quantum dot LCD begin to enter the market in volume.

DisplayWeek 2013: Color is back

Posted on June 6, 2013 by Jeff Yurek

Just back from a great DisplayWeek in Vancouver. Finally had a chance to recover, go through my notes and process everything I saw at the show. Most of the big story lines will be pretty familiar to anyone who followed last years show: TV’s are still getting bigger, OLED TV is still right around the corner, 4K is starting to ship and mobile displays are getting both sharper and more efficient.

DisplayWeek wasn’t all old news though. In fact, just like CES, this year everyone seemed to be talking about color performance. At the annual Display Industry Awards, honors in several categories went to wide gamut display technologies including the Best In Show and Component of the Year awards. And, on the show floor, major manufacturers like 3M, Samsung and LG dedicated significant booth space to wide color gamut or color management technologies.

3M's Quantum Dot Enhancement Film demo at DisplayWeek 2013. Bottom display is using quantum dots to achieve a wide color gamut.

3M’s Quantum Dot Enhancement Film (QDEF) demo at DisplayWeek 2013. Bottom display is using quantum dots to achieve a wider color gamut than OLED at higher brightness and lower cost.

3M demoed several wide color gamut LCDs based on the Quantum Dot Enhancement Film (QDEF) technology that they are partnering with Nanosys to manufacture. Ranging from smartphone all the way up to 55″ TVs in size, these devices were all showing a wider color gamut than OLED with an especially deep red. This seems like a lot of color but 3M says that in developing their Perceptual Quality Metric (PQM), a new analysis tool aimed at helping display makers model how different performance characteristics will affect end user experience, they found that color saturation positively affected the perception of quality.

In Samsung’s neighboring booth, I found a series of comparison demos designed to show that wide color gamut displays can be both accurate and pleasing to the eye. Each demo featured a camera feeding a live image of several colored objects to both standard and wide color gamut displays. In each case the wide gamut display was able to more accurately recreate the color of the objects in front of the camera. They also showed off the new color management capability of their flagship Galaxy S4 smartphone that allows the device to accurately display rec.709 content without oversaturation- something the previous generation S3 struggled with.

Samsung demonstrating the value of wide gamut displays by showing some common colors that fall outside the rec.709 broadcast gamut standard in a series of demos at DisplayWeek 2013

Finally, at LG’s booth, we saw a new LCD color filter design that allows them to cover the Adobe RGB color gamut used by photographers and print professionals.

With all of this buzz, it looks like we’ll start to see wide color gamut displays start to move into the mainstream in ever larger screen sizes over the next half of this year and into 2014.

Color and Visceral App Design

Posted on March 26, 2013 by Jeff Yurek

Visceral refers to the gut, rather than the mind. Our brain may try to talk us out of jumping off a cliff, but as soon as we take that first step into the void, our guts take over. We respond with a rush of emotion and we can’t help but scream from terror or euphoria. It’s a purely visceral reaction. [...]

So here’s my theory: I believe that introducing visceral elements into an app will take it past the point of just being awesome. It will make your app speak to the subconscious, built-in affinity that humans have for the physical properties I mentioned before.

That’s Rob Foster, co-founder of Mysterious Trousers, defining his theory about the importance of visceral elements in application design. The whole piece is well worth reading, especially if you are interested in design or have ever wondered just why Angry Birds is so unbelievably addictive.

In the quote above Rob is talking about the power of little kinetic events in applications like the bounce you get when scrolling to the bottom of a page on the iPhone or the satisfying little “pop” noise you hear when creating a new task in Clear. His point is well made, getting the details of these visceral elements right can clearly take an app from just useful to a truly engaging and even addictive experience for users.

While Rob’s piece focused on the impact of animation and sound, I wondered how color might factor into visceral application design.

Color choice is not just about beautiful graphics- it can also have a powerful physiological effect on us. We have a measurable response to aggressive colors like red, which may even cause a spike in testosterone levels. In fact, recent studies suggest that that the color of a uniform can affect the outcome of an Olympic wrestling match and onscreen colors can even influence how much you pay for something on eBay.

As mobile display technology improves, with more lifelike color and wider dynamic range, application designers may find that color becomes an even more powerful tool to elicit visceral responses from users.

Color at CES 2013

Posted on January 11, 2013 by Jeff Yurek

I’m just wrapping up my visit to CES and it’s been interesting year for display technologies. Amid all the noise about 4K, OLED and 4K-OLED, color performance seems to have quietly worked its way into the conversation. I can’t recall ever having so many relatively technical conversations about color with booth reps from major consumer electronics manufacturers at a CES. It nearly started feeling like a visit to DisplayWeek, that is until I ran into some of the weird, only-at-CES iPhone cases…

I bet we’ll see more color talk next year, especially as 4K content delivery mechanisms and standards begin to mature. In the meantime, these are some of the color-related display stories that caught my eye this week:

Wide gamut content delivery

Sony’s 4K content delivery plans have been one of the most talked about topics here at CES. Less mentioned was Sony’s inclusion of wider color gamut in their standard. Sony reps that I talked to said that both the 1080P Blu-ray disc-based “mastered in 4K” and pure 4K delivery methods would include a wider color gamut. They were not ready to release specifics on gamut size or whether it would meet existing standards like DCI-P3. Still, bringing “expanded color showcasing more of the wide range of rich color contained in the original source” is a move in the right direction for wide gamut.

Color accuracy

Technicolor showed off a color certification program that they hope will incentivize display makers to improve the color accuracy of their panels. Displays that meet or exceed Technicolor’s color specs will get a badge and a copy of partner Portrait Display’s Chroma Tune software, which dynamically controls color gamut to match the application you are using. This means if you open Photoshop on a device with an Adobe RGB 1998 capable display, you’ll get the full, wide gamut. But, if you switch over to watch a YouTube video in your browser, the software will limit the display to rec.709 for the most accurate experience. The advantage was well demonstrated by their e-commerce demo, where a pair of shoes were more accurately depicted on a certified display:

Technicolor’s ecommerce Color Certification demo at CES 2013. The color certified laptop in the middle of the frame more accurately shows the color of the shoes.

Like Sony’s upscaling effort, this kind of technology could help drive wide color gamut adoption by making today’s content compatible with newer displays.

Huge tablets

Panasonic 4K Tablet with sRGB color gamut at CES 2013

Panasonic’s 20 inch 4K/sRGB tablet

Several companies at the show introduced devices in a new class- the 20-plus inch tablet. While there were a lot of hokey multi touch gaming demos (are you really going to play poker with 4 smartphones and a 27″ screen instead of a deck of cards?), the content creation stuff Panasonic showed actually made me think the new form factor shows real promise as a professional tool.

Their tablet, which measures 20 inches on the diagonal, features a 4K IPS panel that covers 100% of the sRGB color gamut standard. Having such a a large canvas with high resolution, accurate color and multi-touch could be great for creative pros like photographers and architects.

Color of the year for 2013 falls outside sRGB gamut

Posted on December 11, 2012 by Jeff Yurek

Pantone recently announced their color of the year for 2013, a deep shade of emerald green that they call “Emerald 17-5641.” It’s a great color but there’s a catch- most displays cannot accurately show it.

Based on data from Pantone’s website, I was able to plot the color in CIE 1931 (xy). As you can see in the chart below, Pantone’s color is well outside the sRGB/rec.709 color gamut standard used by most HDTVs, the new iPad/iPhone and many desktop monitors. These devices will be stuck showing a version of Pantone’s emerald green that’s less saturated and probably a bit more yellow than the real thing.

This is a perfect example of a popular real-world color that falls outside of the sRGB/rec.709 gamut. Unless you have a monitor that’s able to show wider color gamuts, like the DCI-P3 or Adobe RGB standards, you are missing out on a great color.

iPad Content Creation gets more Colorful with FiftyThree’s Paper app

Posted on November 8, 2012 by Jeff Yurek

App developer FiftyThree recently updated one of my favorite creativity apps for iOS, Paper, with an impressive new color-related feature. If you are not familiar with Paper, it’s a sketchbook app capable of making the work of even non-artists like me look gallery worthy with an intuitive and responsive interface.

The new feature, which FiftyThree calls “the biggest leap forward in color controls in the past 40 years,” is a color mixer that allows you to create a wide array of colors within the app just as you would in real life. They say they put a lot of time and effort into making the new mixer feel natural. The Paper color mixer works just like finger painting as a kid, mixing yellow and blue in the Paper app mixer produces green.

The new color mixer, shown at the bottom of this screenshot, lets you mix multiple colors to achieve a much wider palette in the new version of Paper.

This is a great feature that expands the content creation capabilities of an already exceptional app. But, as great as this app is, it’s still limited by the color capability of the device it’s installed on. Even the latest iPad, which can produce 100% of the sRGB color gamut, still only shows about 1/3 of the visible color spectrum.

The experience you will have mixing and creating colors on today’s tablets just will not be nearly as dynamic or visceral as making a physical painting. Not until better, wide color gamut technology is adopted in displays will the digital color experience match the stunning world of color we live in.

DisplayDaily: Is quantum dot lifetime good enough for TV?

Posted on October 5, 2012 by Jeff Yurek

Ken Werner of Display Central has a post comparing the benefits of quantum dots to OLEDs in consumer TV applications. Being the authority on quantum dot displays that we are here at Nanosys, Ken contacted us for an analysis. Here is the explanation our Ph.Ds gave Ken:

OLEDs use organometalic compounds to emit light. They typically have a central metal atom surrounded by organic ligands. The decay issues are the same as with typical organic fluorophores. In the excited state these molecules are very reactive to H₂O and O₂, as well as other small molecules that may be around. Once they react they become a different molecule and they will no longer fluoresce or phosphoresce and give off light. The more blue the light emission, the higher the energy of the excited state, and the more reactive the excited molecule will be. So your blue organic phosphores will have a much shorter lifetime than will red phosphores. The burn-in problem seen in OLED displays, that can be seen after just several weeks of operation with static content, is a manifestation of early blue degradation compared to green and red.

Conventional phosphores like YAG are doped materials. YAG used in white LEDs is actually cerium doped YAG. The cerium atom emits the yellow light and is surrounded by a vast amount of YAG. Quantum dots are similar in that a central core crystalline semiconductor material is used to confine the holes and electrons of the exciton (analogous to the cerium in YAG), and in our material this is surrounded by a thick shell of a different, lattice-matched semiconductor material (analogous to the YAG.) We call this a core-shell Quantum Dot structure. If the lifetime of our materials is less than that of conventional phosphors, it is typically because we have not made a perfectly lattice-matched shell, which may distort the core and cause defects at the core/shell interface that reduces the quantum yield.

The big difference here is that a perfectly made core-shell quantum dot does not have an intrinsic lifetime failure mechanism, whereas the organometallic compounds are intrinsically reactive to their environment, which makes them prone to shorter lifetimes especially at higher energies such as blue.

This is an important discussion, because TVs are a harsh environment for display components, running much hotter and brighter than tablets or mobile phones. You can read the entire post here: http://www.display-central.com/flat-panel/is-quantum-dot-lifetime-good-enough-for-tv/

iPhone 5 color saturation claims

Posted on September 13, 2012 by Jeff Yurek

Display improvements were once again featured at yesterday’s Apple keynote event. The most obvious improvements may have been the larger display and thinner form factor but most interesting to dot-color are the color claims.

Just like the new iPad, Apple claims that the iPhone 5 can display “44% more color saturation.”

Apple SVP of Worldwide Marketing Phil Schiller talks color saturation at the iPhone 5 keynote

Let’s do some simple math to see how the iPhone 5 stacks up against older iPhones and last week’s color performance claim from Motorola.

iPhone 4S IPS LCD: 50% NTSC color gamut (CIE 1931^†)
iPhone 5 IPS LCD: 50% * 144% = 72% NTSC color gamut (CIE 1931)
Motorola Droid Razr Maxx HD AMOLED: iPhone 4S (50%) * 185% = 92.5% NTSC (CIE 1931^‡)

So Motorola is still king of the fall 2012 smartphone color saturation, based solely on marketing claims. That said, I wouldn’t be surprised if they updated their marketing to say that the Droid Razr Maxx HD offers 28% more color saturation than the iPhone 5 once it hits store shelves in a couple weeks. I plan to measure all of the announced devices to verify these marketing claims, but for now, this is all we have to go with.

Apple also claimed to be able to match the sRGB standard used in TV and movies. With the addition of the iPhone 5, nearly all of Apple’s flagship products (with the exception of the MacBook Air) now meet this standard. This means content should look very consistent across all Apple devices and may open up the possibility for serious content creation apps in iOS.

It also means we’re only just now catching up to an average CRT display from circa 1990, as the sRGB standard is based on the capabilities of phosphor materials used in CRTs. And even still, the new displays are only covering about 35% of the range of colors a human eye can see. There’s still plenty of room for improvement in display color performance (as well as updated content delivery standards, but that is a whole different post). Hopefully if we keep on this kind of pace with display enhancements, next year we’ll start to see a push beyond the limits of last century’s color standards.

^† We’re using the long outdated CIE 1931 color space and NTSC 1953 gamut standards here since this is clearly Apple’s reference when they claim 44% more saturation and sRGB coverage. 50% * 1.44 = 72% and 72% of NTSC 1953 gamut in the CIE 1931 color space is also called the sRGB color gamut.

^‡ It is not clear which color space Motorola is referencing; we are assuming CIE 1931/NTSC 1953 for ease of comparison.

Color Space Confusion

Posted on August 14, 2012 by Jeff Yurek

For many who are new to the world of display measurement, the prevalence of two distinct, but often-interchanged color spaces can be a source of confusion. Since my recent post about the color performance of Apple’s new iPad, a number of people have asked about this topic, so I thought it would be worth a closer look.

In the world of displays and color images, there exists a variety of separate standards for mapping color, CIE 1931 and CIE 1976 being the most popular among them. Despite its age, CIE 1931, named for the year of its adoption, remains a well-worn and familiar shorthand throughout the display industry. As a marketer of high color gamut display components, I can tell you from firsthand experience that CIE 1931 is the primary language of our customers. When a customer tells me that their current display “can do 72% of NTSC,” they implicitly mean 72% of NTSC 1953 color gamut as mapped against CIE 1931.

However, from the SID International Committee for Display Metrology’s (ICDM) recent, authoritative Display Measurement Standard:

“…we strongly encourage people to abandon the use of the 1931 CIE color diagram for determining the color gamut… The 1976 CIE (u’,v’) color diagram should be used instead. Unfortunately, many continue to use the (x,y) chromaticity values and the 1931 diagram for gamut areas.”

So why are there two standards, and why are we trying to declare one of them obsolete? Let me explain.

What is a color space?

First, a little background on color spaces and how they work.

While there are a number of different types of color spaces, we are specifically interested in chromaticity diagrams, which only measure color quality, independent of other factors like luminance. A color space is a uniform representation of visible light. It maps the all of the colors visible to the human eye onto an x-y grid and assigns them measureable values. This allows us to make uniform measurements and comparisons between colors, and offers certainty that images look the same from display to display when used to create color gamut standards.

In 1931, the Commission internationale de l’éclairage or CIE (International Commission on Illumination in English) defined the most commonly used color space. Here’s a look at the anatomy of the CIE 1931 color space:

What makes a good color space?

An effective color space should map with reasonable accuracy and consistancy to the human perception of color. Content creators want to be sure that the color they see on their display is the same color you see on your display.

This is where the CIE 1931 standard falls apart. Based on the work of David MacAdam in the 1940’s, we learn that the variance in percieved color, when mapped in the CIE 1931 color space, is not linear from color to color. In other words, if you show a group of people the same green, then map what they see against the CIE 1931 color space, they will report seeing a wide decprepancy of different hues of green. However, if you show the same group a blue image, there will be much more agreement on what color blue they are seeing. This uneveness creates problems when trying to make uniform measurements with CIE 1931.

The result of MacAdam’s work is visualized by the MacAdam Elipses. Each elipse represents the range of colors respondents reported seeing when shown a single color, which was the dot in the center of each elipse:

A better standard

It was not until 1976 that the CIE was able to settle on a significantly more linear color space. If we reproduce MacAdam’s work using the new standard, variations in percieve color are minimalized and the MacAdam’s Elipses mapped on a 1976 CIE diagram appear much more evenly sized and circular, as opposed to oblong. This makes color comparisons using CIE 1976 significantly more meaningful.

The difference of the CIE 1976 color space, particularly in blue and green, is immediately apparent. As an example, lets look at the color gamut measurements of the iPad 2 and new iPad we used in an earlier article. Both charts do a reasonably good job of conveying the new iPad’s increased gamut coverage at all three primaries. But, the 1976 chart captures the dramatic perceptual difference in blue (from aqua to deep blue) that you actually see when looking at the displays side by side:

The increased gamut of the new iPad is worth testing. Next time you find yourself in an Apple store, grab an iPad 2, hold it alongside a new iPad, Google up a color bar image and see the difference for yourself.

So, why do we still use CIE 1931 at all? The only real answer is that old habits die hard. The industry has relied on CIE 1931 since its inception, and change is coming slowly.

Fortunately, CIE 1931’s grip is loosening over time. The ICDM’s new measurement standard should eventually force all remaining stragglers to switch over to the more accurate 1976 standard. Until then, you can familiarize yourself with a decent color space conversion calculator, such as the handy converter we built just for this purpose:

Is creativity the next killer mobile app?

Posted on April 9, 2012 by Jeff Yurek

Since the debut of the iPad in 2010, tablets have become the ultimate content consumption device, but many still to wonder if they’ll ever be capable of replacing notebooks for portable content creation.

While tablets may never truly replace notebooks for all of our content creation needs, especially typing intensive ones, a new crop of apps for iOS and Android are certainly making a case for it.

A little doodle made with the glorious new #Paper app for the iPad from @FiftyThree

(via Brian Taylor from CandyKiller: A little doodle made with the glorious new #Paper app)

Recent creative apps like Paper by fiftythree, Adobe’s Photoshop Touch and Apple’s iPhoto for iOS have just started to scratch the surface of the creative capabilities of powerful mobile devices. These apps show us that mobile creativity, when done right, can harness the unique properties of a touchscreen handheld device to offer new capabilities that a laptop cannot duplicate. Drawing with a stylus in Paper, for example, feels remarkably precise and expressive because of a neat gesture trick- the speed of your pen controls the thickness of the line. Similarly, in Photoshop Touch and iPhoto, editing your photos by actually putting your hands on them, while less precise than a keyboard and mouse, can be a revelation for broad stroke tasks like blending two images.

Tablets clearly have the processing power, the battery life and display resolution necessary to become serious creative tools, but there’s one thing missing: color. Creative professionals normally work on displays capable of showing a range of colors that is as much as 60% wider than even the latest “high color saturation” iPad. Artists need to see the content they are creating in the same vibrant colors they see in the real world. Improving the color performance on mobile devices will make tablets truly worthy of a place in any creative professional’s regular workflow.

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