World Cup Follow-up (Part 2)

After much internet searching and a few cancelled deliveries we finally have our Croatia jersey! A bit too late for the big game but still thought it would be interesting to take a look at the data for both team jerseys:

World Cup Jerseys 3

France vs Croatia jerseys in a 2018 World Cup-themed chromaticity shootout

Like France, Croatia’s jersey happens to fall just inside the BT.709 color gamut. Going back to our original top 10 teams post, it seems like most of the other possible finals matchups would have resulted in a wider color gamut (we did model the Croatian flag red as outside 709).

An interesting follow-up, perhaps for 2022, would be to look at goalie jerseys as well. Goalies wore some of the wildest colors of the competition. France’s Hugo Lorris, for example, wore a super saturated yellow-green for the final match that looked a bit like the tennis ball color we measured recently.

World Cup Follow-up (Part 1)

A few weeks ago I kicked off the World Cup with a survey of the top 10 ranked country’s  colors. At the time, it was impractical to acquire and measure actual jerseys for each World Cup team (32 total) so I limited the survey to top 10 teams and used publicly available data on flag colors under the assumption that jerseys would likely track closely with flags.

Spectroradiomter World Cup Jersey

We’re now down to just two teams so, as promised, I’m back to share some measured data from team jerseys. There is, however, a small issue… Croatia jerseys are sold out everywhere! Probably because it is the first time Croatia has entered the World Cup finals. Luckily, I’ve got one on back-order and will follow-up with yet another update next week, after the big game.

In the meantime, let’s take a quick look at the measured data we do have for France.

France World Cup Jersey Colors

France World Cup 2018 Jersey Colors plotted in CIE 1931

The plot above shows u’v’ coordinates for the three most interesting colors on France’s World Cup jersey: dark blue, light blue and the small pop of red from the back of the collar. As you can see in the plot above these colors actually fall just inside the BT.709 color gamut used for HDTV broadcast. They’re right on the edge though so, if you are watching in HD, you may want to look at having your TV calibrated before the big game for an optimal experience.

The other question that I had after the first post was whether or not the flag data would truly correlate to measured jerseys. In the chart below, I’ve plotted flag data from the original post against new measured data and it seems like my hypothesis held up. At least in the case of France, team colors were reasonably close to flag colors.

France World Cup Jersey vs Flag ColorsLooking forward to providing an update next week on Croatia’s bright red home jersey. In the meantime, may the best team win!

What is the “Color Gamut” of a Fireworks Show?

Editor’s Note: If you read this blog, there’s a decent chance that at some point you’ve gazed up at the impressive spectacle of a July 4th fireworks show and wondered to yourself, “what color gamut, if any, could possibly express all of these deeply saturated, emissive colors??” This week, we’ve got the answers with a timely piece on the chemistry and color of fireworks from guest blogger Allison Harn. Please do not try any of this at home!

Updated 7/6/18 to correct a typo in the chemical compound chart. Hat tip to Matt B. for catching the error!


Fireworks

Image credit: Fireworks via Flickr user ·tic∙ under CC License

If You Are Someone Who Doesn’t Like Fighting After-Show Traffic, Viewing Firework Displays On Tv Is About To Get Better

Ever noticed how disappointing it is to watch fireworks on your home TV compared being out experiencing a live show? If you’re a true fireworks enthusiast, nothing can replace that brilliant burst of color in the sky, followed by a brief moment of anticipation before sound finally catches up to light and the loud THUMP pounds through your chest.

The perfect combination of sound and color are what makes fireworks shows memorable. While I can’t shed light on how sound systems compare to the real deal, I do have insight on why fireworks colors fail you so horribly on current TV’s.

First, A Bit Of Background Chemistry

If you ever took an introductory chemistry course, you might remember performing flame tests on solutions. Electrons get excited by energy from the flames and when they lose that energy, they emit light at specific wavelengths. Each element has its own unique colors that are produced (copper ions emit blue-green; lithium ions emit crimson red). Fireworks compositions work similarly, though it’s a little more complex.

 These grey pellets, called In the pyrotechnics world, the materials that produce colors are collectively called “stars”. The composition of stars varies greatly; it seems like there are more recipes out there for creating a particular color of star as there are for your favorite type of cookie. In the end though, they mostly look the same: black or grey pellets shaped into small cylinders or spheres.

Fireworks and Chemistry 2018 Update
The magic happens when these are ignited. The ingredients combine together at high energies to produce compounds that emit visible light. There are many different color emitters, but the most intense colors come off of the stars that are able to produce Strontium Monochloride (SrCl) for red, Barium Monochloride (BaCl) for green, Copper(I) Chloride (CuCl) for blue, and Calcium Monochloride (CaCl) for orange. These are unstable compounds that are formed in the high temperatures during the chemical reaction.The most remarkable part about this though is that the wavelengths that these compounds emit cannot be displayed by your TV. Current HD TV’s capture only a small part of what the human eye can see. The colors listed above fall almost completely outside the current HD broadcast color space and two of them are beyond even the newer UltraHD TV color space.

Color Fireworks Updated 2018_2.jpeg.001

“Color Gamut” of a fireworks show, plotted in CIE 1976 (u’v’) with comparison to HDTV and BT.2020 color gamuts.

Colors that lie outside the HD TV region in the above chart cannot be accurately displayed by an HD set. These TVs distort what you see by remapping deeply saturated colors so that they fall within the display’s limited color gamut (editor’s note: we detailed how color spaces work in “Color Space Confusion” from 2012). What you see on an HD TV is simply less colorful, less realistic than what you would experience in person.

This is where Quantum Dot TV’s come in. Newer UltraHD TV’s that use this technology can reproduce a much larger range of colors, over 90% of the BT.2020 color space shown above. For fireworks shows, this means that you would be able to experience the true oranges and blues that are part of the displays. Current technology cannot completely capture the red and green colors, but it is much closer than it used to be. These colors will be distorted much less than HDTV’s, providing a significantly improved experience.

When it comes to the 4th, you’ll still find me sitting out in the front row. But if you prefer watching fireworks from the comfort of your own living room, it’s about to get much better. Your pets will probably thank you too.

Reference: http://www.jpyro.com/wp-content/uploads/2012/08/Kos-710-731.pdf

Reposted from the Nanosys Blog, 2016

About The Author

allisonAllison Harn is the Manufacturing Operations Analyst at Nanosys. She has a background in chemistry and before coming to Nanosys taught high school chemistry for several years. Her current position supports operational excellence in quantum dot manufacturing by promoting continual improvement.