Misconceptions are persistent because the question is simple. But simplicity can hide important differences between mixing systems. The most common problems show up fast once you try mixing.
Misconception 1: “Blue is made from two wavelengths with no blue involved”
Sometimes this happens in special cases for light perception, but for practical paint mixing and most real-world materials, it’s not reliable. Blue is a perception of reflected light; pigments and inks control which parts of the spectrum they reflect.
So if you start with no “blue-leaning” pigment (or no blue channel in a digital model), the result may drift toward purple, gray, or a muddy mix.
Misconception 2: “Mixing red and yellow always creates blue”
Red and yellow are not “blue neighbors.” In subtractive pigment mixing, they tend to create warm tones. If you want a blue outcome with pigments, you typically need a blue-leaning component somewhere in the recipe or you need system-specific modeling that accounts for absorption.
That’s why advice that ignores the medium often contradicts itself.
