Wet Collodion Process

British · Wet Collodion / Ambrotype 1851–1880

The photographer had about ten minutes from coating the plate to developing it, which meant the darkroom had to travel to the subject. This is why war photographers of the 1850s and 60s arrived with a wagon.

The Wet Collodion Process color palette

The colours reconstructed for this artist, with the reasoning behind each. Each swatch is an interpretation of the materials behind it, not a sample taken from a single work. How the palettes are made

Glass plate tone

Varnish amber

Iron toned shadow

Ambrotype cream

Collodion pour edge

Battlefield grey

Pigments used: Silver

Origin

Introduced by Frederick Scott Archer in 1851 and deliberately not patented, which is much of why it spread so fast. It combined the daguerreotype's sharpness with the calotype's reproducibility and displaced both within a decade. It was the dominant process for roughly thirty years, covering the American Civil War, the surveys of the American West, and the industrialisation of studio portraiture through the carte de visite.

Technique

A glass plate is coated by hand with collodion — nitrocellulose in ether and alcohol — containing iodide salts, then sensitised in a silver nitrate bath, exposed while still wet, and developed immediately, because the plate loses sensitivity as it dries. The whole sequence, from coating to fixing, has to be completed in a quarter of an hour. Variants of the same chemistry produce the ambrotype, an underexposed negative backed with black to read as a positive, and the tintype on lacquered iron, which was cheap, fast and durable enough to post home.

The palette

Cool, silvery and high in contrast, with a distinctive tonal signature caused by the emulsion's blue sensitivity: skies go blank white, skin is rendered pale, freckles and red lips darken, and blue eyes photograph unnaturally light. Prints from collodion negatives were usually albumen, which adds a warm brown. The characteristic edge artefacts — pour marks, fingerprints, uneven coating at the plate corners — are visible in most surviving work and are now often imitated deliberately.

Legacy

It produced the largest body of nineteenth-century photography and the great survey and war archives. Dry gelatin plates, which could be manufactured in advance and stored, made it obsolete in the 1880s and effectively created the amateur market. Wet plate has been revived by contemporary practitioners for exactly the qualities that made it difficult — the hand-coated surface, the singular object, the long exposure that requires a sitter to hold still.

By Pigmentoria · Published 6 August 2026 · Palette: interpretive reconstruction

Working at the same time

Elsewhere in the atlas, in other movements and other media, these were the hands at work during the same years.

Gustave Courbet19th-Century Realism & Tonalism John Everett MillaisRomanticism Albumen Print ProcessAlbumen Print Gustave MoreauSymbolism James Abbott McNeill Whistler19th-Century Realism & Tonalism Winslow Homer19th-Century Realism & Tonalism