Short answer: Grisaille underpainting means painting your model first in greys only — a pure black-and-white value study — and then glazing transparent colour (a thin, see-through wash that lets the grey show through) over the top. In other words, you separate light and shadow from colour. The payoff is smooth, painterly results on busts, portraits and display pieces, especially on skin and cloth.
The name comes from the French "gris," meaning grey, and the method is borrowed from classical oil painting. The idea behind it is simple: the human eye reads a form from value (its light-to-dark relationships) first and only notices colour second. Grisaille leans right into that — you paint a flawless grey "sculpture," then dress it in colour. It is usually overkill for a 28mm tabletop army, yet it becomes a very strong choice for larger scale and cabinet pieces.
What is grisaille underpainting and what is it for?
Let's take the two words one at a time. Grisaille is the process of painting in greys, which produces a monochrome, single-colour image. Underpainting, meanwhile, is the process of building light and shadow before your base coats. Combine the two and you end up with a black-and-white value skeleton first, then colour.
So what does it buy you? Above all, it removes the burden of managing colour and value at once. Most painters stall on transitions because they are fighting to hit the right hue and the right brightness in a single stroke. Grisaille splits those problems apart: value only first, colour only second. That way you solve each one calmly, on its own. The surface you end up with is smoother, more consistent, and carries that painterly quality you see in classical paintings.
This technique is a close relative of Zenithal Priming. In fact, you can think of zenithal as the fast, airbrush version of grisaille underpainting; full grisaille is a greyscale built by hand, coat by coat, with far more control.
How does it work?
The secret is transparency. A transparent glaze lets the grey beneath show through. So when you lay a red glaze over a light-grey area, that area turns light red; a dark-grey area turns dark red instead. The colour simply inherits the value structure that is already underneath it.
And that is the whole trick: you perfect the value on its own, with no colour confusion. During the greyscale stage you can stack as many layers as you like, soften the transitions, and dial in the contrast — all without making a single colour decision. You can see clearly whether an area is light enough or dark enough, with no colour fooling your eye. Once the value is right, the transparent colour on top preserves that rightness; if the value is wrong, the colour faithfully inherits the mistake too.
As Forgone Miniatures (inspired by Marco Frisoni) sums it up: grisaille is the process of painting in greys to produce, in effect, a monochrome image, while underpainting is the process of building light and shadow before your base coats. In short, you build the light and shadow in monochrome first, then add colour only as a "costume" at the end. No colour glazed over bad value will rescue a piece.
How do you do it step by step?
The workflow really comes down to two clear stages: first you build the grey value, then you glaze the colour. Don't rush it — most of the work hides in the first stage.
- Build the greyscale: Paint the model in black-and-white tones. Place the highlight (the lightest light), the shadow and the mid-tones smoothly enough to define the form completely. Do it with layering (building up thin tonal coats), glazing or airbrush. This stage is the skeleton of the piece.
- Perfect the value: Before you touch any colour, make sure the greyscale's volume, transitions and contrast are right. The effort you spend here decides most of the result.
- Glaze the colour: Apply transparent colours — glaze, Contrast, or heavily thinned acrylic — gradually over the greyscale. The colour will inherit the value beneath it.
- Add saturation and warmth: Next, enrich it with local warm-cool glazes; a touch of red in the skin, a little blue in the shadows. This step is what keeps the piece from looking flat.
- Detail and final accents: If needed, reinforce the brightest highlight and the darkest shadow in colour this time, to bring back the contrast the glazes softened.
To understand the bridge between greyscale and colour, read Glazing and Underpainting Methods; the latter also covers coloured variants like verdaccio (green) and brunaille (brown).
Which paints and brushes do you need?
The good news is that grisaille is not an expensive technique; the real cost is patience, not gear. Even so, thinking of two separate paint sets for the two stages makes life much easier.
- Greyscale stage: Black, white and a few mid-grey acrylics. You can also mix just two of them to make your own intermediate tones.
- Colouring stage: Transparent colours, a glaze medium, or Contrast/Speedpaint-style paints. These already work semi-transparently, so they won't smother the value underneath.
- Brush: A good synthetic or sable brush that holds a fine point; a sharp tip matters for smooth transitions.
- Wet palette: Almost essential for keeping your glazes at a consistent thinness.
- Airbrush (optional): Ideal if you want a fast, ultra-smooth greyscale.
Since glazing is the heart of the colour stage, your medium choice matters too; the Glazing Mediums guide explains exactly what to thin with what.
Most common mistakes
Here is the catch: most grisaille mistakes happen in the first stage, while everything is still monochrome grey, and they only blow up once the colour arrives. These are the most common ones.
- Sloppy greyscale: Rushing the value and jumping straight to colour. Bad value means a bad result; no colour saves it.
- Opaque colour: Mixing your colour glazes too heavily and smothering the value below. Yet transparency is the lifeblood of the technique.
- Flat colour: Skipping the warm-cool richness. The value can be great, but the colour comes out lifeless.
- Wrong scale: Attempting full grisaille on a 28mm tabletop model. At that size it is usually unnecessary; there, Zenithal Priming or Slapchop is far more efficient.
Pro tips
What really raises the quality of a grisaille piece is a handful of small habits. They all come straight from the practice of experienced painters.
- Exaggerate the contrast a little: Push the value range slightly wider than you think you need in the greyscale stage. The colour glazes on top will naturally soften the contrast a touch.
- Check with a photo: Photograph the grey model before you add any colour. A screen exposes the value distribution mercilessly, so it is the easiest place to catch the gaps.
- Pick the right scale: Grisaille shines on busts and large scale; on small tabletop models, zenithal or slapchop stays more efficient.
- Try it on skin first: Grisaille is very strong for skin, so a face is a great lab for your first attempt. For more, see Face & Skin Painting.
Frequently Asked Questions
Are grisaille and zenithal the same thing?
They are close relatives, but not the same. Zenithal is a quick grey value layer sprayed from above with an airbrush. Full grisaille is a greyscale built by hand, coat by coat, with far more control. In short, zenithal is the sped-up version of grisaille logic.
What skill level is grisaille?
It generally counts as advanced. Managing two separate stages — value, then colour — in sequence and working with transparent glazes does take some experience. That said, the logic is simple, and you can grasp the core idea at an intermediate level just by trying it on a single area like skin.
Does grisaille make sense for a 28mm tabletop army?
Usually no. Full grisaille is slow, and the difference is hard to see on small figures. At that scale, Zenithal Priming or Slapchop gives you the same value-first logic far faster. It is better to save grisaille for busts, display and large-scale work.
Can I use Contrast or Speedpaint instead of a glaze?
Yes, easily. Contrast and Speedpaint-style paints already work semi-transparently and inherit the value underneath, so they sit well over a greyscale. Just remember to build the warm-cool balance area by area; a single flat coat of Contrast can sometimes leave the colour looking flat.
How much contrast should I put in the greyscale stage?
A little too much. As the colour glazes stack up, they naturally compress the value range and soften the contrast. So if you leave the highlight a touch brighter and the shadow a touch darker in the grey stage, the balance lands right once the colour is on.
Why is grisaille so good for skin and cloth?
Because skin and cloth are the surfaces where the eye most expects smooth value transitions. When you separate value from colour and perfect it first, the colour on top preserves that smoothness. The result is clean, painterly skin or deeply folded, natural-looking cloth.
Key takeaway and next step
To put it in one line: build the value flawlessly in grey first, then dress it in colour with transparent glazes. Most of the work lives in the greyscale stage, so check it with a photo, exaggerate the contrast a little, and only then move on to colour. This method makes a real, visible difference on busts and display pieces.
If you're ready to try it, you can find the black-and-white acrylics, glazing mediums, Contrast paints and good brushes grisaille needs in our paints, brushes & hobby supplies section.