Monthly Archives: May 2019

The Tennis Ball Color is…5GY (Chartreuse)

Tennis ball in standard color
Tennis ball used in 2011 Japan Open. Photo by Christopher Johnson. Licensed by Creative Commons.

Today the most recent color debate is about those bright fluorescent tennis balls – the question being are they yellow or green? The answer probably is …both.

Focal Colors

This issue points to how cultures do divide color space and supports the Berlin and Kay theory of focal color. Although humans can see thousands, if not millions of colors, most languages assign primary names for only a small percentage of them. In English, two of these color words are “yellow” and “green” (along with red, blue, orange, purple, white, black, brown).

Of course these colors are umbrella terms for a range of colors. For instance, we may speak of pine green (dark and a little blue), sea green (pale green), olive green (like the green olive) and so forth. But when “green” stands alone, we may be thinking of the prototypical or focal color – a bright green associated with emeralds, leaves or “Kelly green”. This green is what is normally seen in national flags, corporate logos or many sports team logos.

Similarly, although yellow comes in different shades including mustard (slightly darker), lemon (slightly paler) and saffron (with a touch of orange), the word “yellow” refers to the shade of yellow used in many national flags and logos such as John Deere (tractors). The focal colors are also what is taught to children when they are exposed to color words as can be seen in the sample images below.

What About the Tennis Ball?

An answer that I think many people have guessed is that the color of the fuzzy round object is right on the mental border between a bright yellow and a yellowish pale spring green. If “yellow” or “green” are the only available options, it appears some think yellow and others green. To be clear, the International Tennis Federation (ITF) (and tennis player Roger Federer) calls this color “yellow”, but if you want an ITF approved model, it may be green.

Some other factors to consider is that lighting may make a tennis appear greener in some photos and yellower in others. Even in the Japan Open photo, the ball appears yellower in direct light and greener in the shadow.

For me, I couldn’t really classify this color as either yellow or green…just fluorescent and perhaps fluorescent chartreuse. Interestingly a lesson artists have to learn about color is that 1) there are a lot of them and 2) most professional color wheels have lots of color divisions on the edge, often including chartreuse (or 5GY in the Munsell system).

From a linguistic point of view, this does show what happens when the color of an object sits on a mental color border, and apparently it’s not pretty.

P.S. Japanese Blue Traffic Lights

Ever heard that Japanese label the Go traffic light as “blue” (ao) even when they’re the same color as U.S. traffic lights? There are differences between the English and Japanese color system, but if you look closely, you’ll see that traffic light “green” is actually pushed towards a bluer (cyan shade). In some photos, the correct color may be “cyan.”