The first decision is already made
Before a mark is laid, the surface is making choices. A ground — the preparatory layer that seals the support and provides a working surface — controls absorbency, texture, and above all, tone. A bright white chalk ground in gesso bounces light back through transparent glazes; a mid-toned imprimatura — a thin, tinted first wash — kills that bounce and drops the whole painting into a lower, warmer key. Neither is neutral. Both are positions.
The history of grounds runs alongside the history of what painters wanted light to do. Early panel painters built up layers of animal-skin glue and chalk or gypsum, sanded to near-smoothness so that tempera would grip and translucent oil passages would glow from beneath. When oil paint displaced tempera in northern European practice during the fifteenth century, oil-based primings began to replace absorbent chalk, producing a less thirsty surface that let paint slide rather than sink. The working experience changed entirely.
By the nineteenth century, commercially prepared canvases arrived already primed, typically with lead white ground in oil. This was genuinely convenient: it freed painters to work outdoors without mixing grounds in advance. But it was also a constraint disguised as a service. The commercial ground was formulated for general use — moderately absorbent, middle-bright, consistent. A painter who wanted a dark ground, a coloured imprimatura, or the extreme absorbency of raw linen was now opting out of a default rather than making an unfettered choice.
The twentieth century introduced acrylic gesso — a misnomer, since it contains no gypsum, only acrylic polymer and titanium white — which dries fast, stays flexible, and became the standard for stretched canvas. Brilliant and slightly plastic in surface character, it shifts the key still higher. Painters who find commercial acrylic grounds too cold or too bright often apply a tinted isolation layer on top, effectively reconstructing the imprimatura that pre-primed convenience had removed.
The ground is the first argument the painting makes about tone. Buying a pre-primed canvas means accepting someone else's opening line.
Materials and method
- Gesso
- traditional ground: animal-skin glue bound with chalk or gypsum, highly absorbent, used on rigid panel supports
- Imprimatura
- thin tinted wash applied over a ground to lower tone and reduce absorbency before painting begins
- Oil priming
- lead white or similar pigment in oil, less absorbent than chalk gesso; became standard on commercial canvas in the nineteenth century
- Acrylic gesso
- modern commercial priming; acrylic polymer with titanium white; flexible, fast-drying, not true gesso despite the name
Hung floor to cornice, a picture placed high was said to be skied: admitted, and effectively unseen.
Photo: Shakyamuni Buddha with Avadana Legend Scenes - Google Art Project · Wikimedia Commons
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