How to mix clean oranges and purples (and why yours go dull)
Orange
Clean orange needs a warm red and a warm yellow: Cadmium Red Light (or a Scarlet/Vermilion hue) with Cadmium Yellow Medium or Deep. Both already lean towards orange, so nothing cancels. Start with the yellow and add red in small amounts — red is the stronger tinter and the mix swings quickly.
Use a cool red (Alizarin) or a cool yellow (Lemon) and the orange greys off: the violet in Alizarin and the green in Lemon are both enemies of orange. That greyed orange is not useless — it is close to the color of terracotta, brick and autumn leaves — but it is not a clean orange.
Burnt OrangeRecipe by paint setCoralRecipe by paint setTerracottaRecipe by paint setRustRecipe by paint set
Purple
Clean violet needs a cool red and a warm blue: Alizarin Crimson, Permanent Rose or Quinacridone Magenta with Ultramarine. Mix about 1 : 1 and tint a little with white to see the hue; neat it is nearly black. Dioxazine Purple from the tube is cleaner than almost anything you can mix and extremely strong — a dab goes a long way.
Cadmium Red + Ultramarine makes a dull plum; any red + Phthalo Blue makes a greyed navy-violet. Again, useful colors (shadows, distant hills, eggplants) but not clean purple.
LavenderRecipe by paint setMauveRecipe by paint setMaroonRecipe by paint setNavy BlueRecipe by paint set
Green, briefly
The same logic: cool yellow (Lemon) + cool blue (Phthalo) for the cleanest green; cool yellow + Ultramarine for a softer one; warm yellow + any blue for an olive. The greens guide covers the strength problem that makes green worse than the other two.
Moss GreenRecipe by paint setForest GreenRecipe by paint setSage GreenRecipe by paint set
Lightening a secondary without killing it
White greys secondaries fast, especially violet and orange. For a light orange add a little yellow with the white; for a light violet add a touch more of the cool red; for a light green add a little lemon. Keeping the warm parent in the tint holds the chroma.
PeachRecipe by paint setLavenderRecipe by paint setSky BlueRecipe by paint set
Why tube secondaries are still worth owning
A single-pigment orange (Cadmium Orange, Pyrrole Orange), violet (Dioxazine) or green (Phthalo, Viridian) is cleaner than any mix because there is only one pigment absorbing light. Use them for the few places that need full chroma and mix everything else. The calculated recipes on this site use tube secondaries when a set has them and two-primary mixes when it does not, which is one reason a Winton recipe and a Magicfly recipe for the same color look different.
Questions
What two colors make a clean orange?
Why does my purple look brown?
How do I make a bright purple without buying Dioxazine?
