What makes a colour pastel
A pastel is a pale tint: a small amount of colour in a lot of white. Pastels are light in value and soft in saturation, which gives them their gentle, airy feel: mint, blush, powder blue, lemon cream, lavender.
Colour into white, not white into colour
Start with a pile of Titanium White and add the colour a little at a time. Going the other way, you need a huge amount of white to lighten a strong colour, and you end up mixing far more paint than you need.
That's why pastel recipes show ratios like 40 parts white to 1 part colour. It is normal: strong pigments like Phthalo Blue and Quinacridone Magenta only need a trace.
Why white changes colour
Adding white doesn't just lighten a colour; it also cools it and makes it chalkier. A red tinted with white goes towards pink, not a lighter red. If a pastel looks too cold or flat, add a tiny amount of a warm yellow or red to bring it back.
Using pastels
- Pastels need value contrast. A painting that is all pastel can look washed out, so anchor it with a few mid or dark tones.
- They suit high-key work: misty mornings, florals, light interiors.
- Titanium White is opaque, so pastels cover well, which is useful for highlights and corrections.