Yellow is about 575nm, while cyan is 490nm if this diagram is correct: https://en.wikipedia.org/wiki/File:PlanckianLocus.png https://en.wikipedia.org/wiki/File:

Yellow is about 575nm, while cyan is 490nm if this diagram is correct: https://en.wikipedia.org/wiki/File:PlanckianLocus.png https://en.wikipedia.org/wiki/File:PlanckianLocus.png