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Perfecting acrylic skin tones from a limited palette
Why your skin tones go chalky — and the three-tube base mix that fixes it, in any skin range.
Read →An oil paint colour matching workflow that actually saves time
A repeatable process for matching any reference colour from the oils you already own, without wasting a tube.
Read →How to organise a paint palette before you start painting
A layout system that keeps your mixes clean, your darks dark, and your whites uncontaminated all session.
Read →Colour wheel
The wheel orders hues so opposites are complementary. Primaries (red, yellow, blue) can't be mixed from other colours; secondaries (orange, green, violet) are equal mixes of two primaries; tertiaries sit between them.
Complementary colours
Opposites on the wheel. Mixed together they neutralise toward grey — useful for muting overly bright passages and for painting believable shadows. Placed side-by-side they intensify each other.
Tip: instead of black, mix a colour's complement into it for a more lifelike, chromatic shadow.
Other schemes
- Analogous — 3 neighbours on the wheel. Harmonious, calm (e.g. yellow, yellow-orange, orange).
- Triadic — 3 colours equally spaced. Vivid, balanced (e.g. red, yellow, blue).
- Split-complement — a colour plus the two neighbours of its complement. Strong contrast, less tension than a direct complement.
- Limited palette — 3–6 paints chosen for unity. Forces mixing skill and produces cohesive paintings.
Temperature
Every hue has warm and cool versions. A "warm" red leans orange (Cadmium Red, PR108); a "cool" red leans pink/violet (Quinacridone Magenta, PR122). Choosing the right bias controls how a mix shifts:
- • Warm + warm → bright secondary (warm red + warm yellow = vivid orange).
- • Warm + cool → muted secondary (warm red + cool yellow = duller orange — they fight each other).
- • Two cool primaries → cleanest violets/greens (cool red + cool blue = clean violet).
Value structure
Value (lightness) does more work than hue. A painting with strong value structure reads from across the room. Squint at your reference — what you still see is the value pattern.
Aim for a clear "dark / mid / light" plan before colour. Reserve your darkest darks and lightest lights for focal points.
Opacity & transparency
- Opaque (Cadmiums, Titanium White, most earths) — covers what's underneath. Best for solid forms and corrections.
- Semi-transparent — partial coverage; useful for scumbling.
- Transparent (Phthalos, Quinacridones, Dioxazine Violet) — light passes through. Best for glazing and luminous shadows.
- Staining — bonds aggressively; hard to lift. Phthalos and Quinacridones stain.
In watercolour: transparency = luminosity. In oil/acrylic: layer opaque over transparent darks for depth ("fat over lean" in oils).
Pigment codes
The Colour Index uses letter+number codes that identify the actual pigment, regardless of marketing name. P = pigment, then a letter for hue family (B blue, R red, Y yellow, G green, V violet, W white, Bk black, Br brown), then a number. Two tubes with the same code behave the same way, even from different brands.
| Code | Common name | Temperature | Opacity | Lightfastness |
|---|---|---|---|---|
| PB29 | Ultramarine Blue | Warm blue | Semi-transparent | Excellent |
| PB15 | Phthalo Blue | Cool blue | Transparent (staining) | Excellent |
| PG7 | Phthalo Green | Cool green | Transparent (staining) | Excellent |
| PG36 | Phthalo Green YS | Warm green | Transparent | Excellent |
| PY35 | Cadmium Yellow | Cool yellow | Opaque | Excellent |
| PY3 | Hansa Yellow Light | Cool yellow | Semi-transparent | Good |
| PY74 | Hansa Yellow Medium | Warm yellow | Semi-transparent | Good |
| PY42 | Yellow Ochre | Warm earth | Opaque | Excellent |
| PR108 | Cadmium Red | Warm red | Opaque | Excellent |
| PR254 | Pyrrole Red | Warm red | Semi-opaque | Excellent |
| PR122 | Quinacridone Magenta | Cool red | Transparent (staining) | Excellent |
| PR101 | Burnt Sienna / Indian Red | Warm earth | Semi-opaque | Excellent |
| PR206 | Quinacridone Burnt Orange | Warm earth | Transparent | Excellent |
| PBr7 | Raw / Burnt Umber | Cool earth | Semi-transparent | Excellent |
| PV19 | Quinacridone Rose/Violet | Cool | Transparent (staining) | Excellent |
| PV23 | Dioxazine Violet | Cool | Transparent | Good |
| PW6 | Titanium White | Cool white | Opaque | Excellent |
| PW4 | Zinc White | Cool, soft | Semi-transparent | Excellent |
| PBk7 | Lamp / Carbon Black | Cool black | Opaque | Excellent |
| PBk9 | Ivory / Bone Black | Warm black | Semi-opaque | Excellent |
Tips by medium
Slow drying — let layers tack up before reworking. "Fat over lean": more oil/medium in upper layers to avoid cracking. Wipe brushes between mixes; don't pollute your whites.
Dries 1-2 values darker than wet. Work fast or use a retarder. Glazing medium turns any opaque into a transparent glaze. Phthalos stain — keep a dedicated brush.
Plan lights first — you can't add white back easily. Wet-on-wet for soft edges, wet-on-dry for crisp ones. Lift mistakes with a damp clean brush before they dry.
Like opaque watercolour. Rewets even after drying — handy for blending, risky for layering. Slightly dulls when dry. Excellent for flat colour and illustration.
Permanent once dry. Build value with dilution or hatching. Combine with watercolour for line+wash.
Glossary
- Hue
- The colour family — red, blue, etc.
- Value
- How light or dark a colour is.
- Chroma / Saturation
- How pure or intense a colour is (vs. neutral grey).
- Tint
- Hue mixed with white — lighter, often less chromatic.
- Shade
- Hue mixed with black — darker, often muddier.
- Tone
- Hue mixed with grey — softer, more sophisticated.
- Gamut
- The total range of colours a palette can mix.
- Glaze
- A thin transparent layer over a dry layer; shifts the colour underneath.
- Scumble
- A thin broken layer of opaque/semi-opaque paint over a dry layer.
- Local colour
- The 'true' colour of an object before light/shadow.
- Lightfastness
- Resistance to fading from light exposure (I = excellent).
- ΔE (Delta E)
- Perceptual distance between two colours. Under ~2 is indistinguishable.