Over the Rainbow: Primary vs. Secondary Colors

primary colors, secondary colors, color theory, optics, Eyewire, citizen science, Eyewire Over the Rainbow

Eyewire has explored color models before, including our RGB vs. CMYK showdown. But where light-dependent technology is concerned, the RGB model is what unequivocally dominates. Our modern cameras, computers, phones, TVs, projectors, and multicolor LED fixtures all operate from the premise that if you create a blend of red, green, and/or blue lights, adjusting saturation levels as needed, then you can display an enormous variety of the colors that you want your device to show, thus eliminating the need to separately emit any colors outside the primary set.

It’s important to note that blending red, green, and/or blue light will not give you every color in the world! The moment you choose exactly which hues of those colors that you’re going to blend, your blending options will be limited accordingly. For example, your red is on the more orangey side, you can use a very pure green and still allow yourself to create vibrant yellows, but once you blend that same red with blue, it may be harder to get all the shades of purple that you’d like. Nevertheless, the RGB model has robustly served the needs of our digital world for many decades.

Within that framework, what’s your own color vibe? Let’s take a closer look at the primary and secondary colors available in this model.

Primary Colors

  • Red – The longest wavelengths on the spectrum that the human eye can see. On its own, the color is often used as an “alert” symbol because of its correspondence with blood and poisonous plants. But in many cultures it’s also a symbol of love, luck, and health (rosy cheeks!).
  • Green – The middle hues of the visible spectrum, and as mentioned elsewhere, it’s the easiest for our eyes to differentiate and the most likely color to soothe a restless mind. Makes perfect sense since green suggests a lush, prosperous landscape!
  • Blue – Not quite the shortest wavelengths we can see, but close. Blue also suggests a variety of concepts in various cultures. To some people it may mean serenity, purity, or nobility; to others it may signify sadness or death.

Secondary Colors

  • Yellow – Created by blending red and green light. Across the world, yellow is frequently associated with happy emotions and wise harmony. However, it too can be an “alert” color, because yellow is the easiest color to perceive at a distance.
  • Cyan – Created by blending green and blue light. As mentioned in our Accuracy Happy Hours post, different cultures distinguish between the colors green and blue at various points on the spectrum. Therefore, you may think cyan just looks like a bluish shade of green, or it looks like a greenish shade of blue. Regardless, as far as the RGB color model goes, it’s a unique color.
  • Magenta – Created by blending blue and red light. Because this color involves combining the far ends of the visible spectrum, magenta is known as extra-spectral, i.e. it can’t appear on the spectrum itself. However, our eyes can still perceive it because of how we can perceive red and blue.

Is your favorite color on Team Primary, or is it more of a blend? Choose your team soon because the competition starts at 11:00 AM EST on 2/21 and goes for 48 hours! Bonus information is detailed in your notifications.

Swag: The top scoring player on the winning team wins a t-shirt, plus a sticker/magnet set! Second and third place on the winning team will each also win a sticker/magnet set.