You may hear advice like “mix X and Y to get blue.” Sometimes it’s true in a specific system, but not in others. A big reason: in pigment mixing, there are fewer “guaranteed” outcomes than in light mixing. Two different paint brands or two different yellows can push your result toward green, gray, or purple.
Also, the word blue covers a wide range: cobalt, ultramarine, cerulean, navy, periwinkle, and more. A two-paint mix might land near one of these, while missing others.
Hue vs. brightness vs. saturation
Beginners often focus on hue (“make it blue”) and forget brightness (“make it lighter”) and saturation (“make it vivid”). Two-color recipes usually manage one or two of those dimensions, not all three at once.
That’s why blue + white works so well: it primarily changes brightness while keeping blue as the dominant hue.
