The anthotype is a photograph made with plant juice and sunlight, using no chemistry at all. You crush petals, berries or leaves, brush the juice onto paper, lay a positive transparency on top, and wait. It is the only fully non-toxic photographic process: nothing to handle with gloves, nothing to pour down a sink, nothing to take to a waste facility. It is also the slowest and the most fragile — the two go together, and that is not a flaw to be fixed but the nature of the process itself.
1842: Herschel names an old observation
That plant colours fade in sunlight is no discovery: every dyer has known it for centuries, and sees it as a problem. The scientific act consists in turning the problem into a process. In the 1840s Mary Somerville studied the light-sensitivity of plant juices; John Herschel — the astronomer we also owe the cyanotype to — took up that work and named the result anthotype, from the Greek anthos, "flower", in 1842.
So the same man signed, within a few years, both the most robust process in alternative photography and the most fleeting. The cyanotype forms a mineral pigment — Prussian blue — that lasts for centuries. The anthotype merely removes colour from an organic material, and that removal never stops. The two processes illuminate the same question from opposite ends: what, in an image, is meant to last?
The inverted principle: light destroys instead of building
This is the one thing to understand, and it governs everything else. In a cyanotype, a carbon print or a gum bichromate, UV makes something: a pigment forms, a layer hardens. So you expose under a negative, whose dense areas protect what must stay white.
In an anthotype, the colour is already there — the juice has been brushed on and dried. UV does not form it, it destroys it. So you must expose under a positive: its dark areas shield the juice, which stays coloured; its clear areas let light through, whitening the paper. Using a negative would give an inverted image — the classic mistake for anyone coming from cyanotype, and the only one not to make. Everything else, tight contact under glass and sun exposure, is rigorously identical.
Which plants, and why they are not equivalent
Almost anything that colours strongly will serve: red cabbage, beetroot, spinach, turmeric, hibiscus, poppy, blackberry, elderberry, tulip petals. But two juices of comparable hue can demand exposure times differing by a factor of a hundred. It is not the intensity of the colour that governs, it is the fragility of the molecule carrying it.
Herschel had already noted that marigold and corchorus japonica were among the fastest, shifting within minutes of clear sunshine. At the other extreme, red cabbage or beetroot juice commonly needs one to four weeks behind glass. There is no universal reference table, and there cannot be one: juice concentration, harvest season and variety make the result vary from one extraction to the next. The only reliable method is a test strip coated with the same juice as the print.
What the anthotype will never do
No fixer exists for the anthotype, and none can: the mechanism that makes the image is precisely the one that will destroy it. A print left in daylight fades within months. The only viable conservation is dark storage and brief, dimly lit display.
This is a constraint to accept at the outset rather than to work around. Common practice is to scan the print as soon as it is judged finished: the file becomes the archive, the sheet remains a transient object. Put differently, the anthotype is not an archival process — it is an experiential one, and it is worth what it teaches about everything else.
What you need, and what Vision Picturale can supply
The juice you will make yourself: it is the heart of the process and there is nothing to buy for it. Two elements do matter, however, and they are the same as for cyanotype.
- Absorbent paper, not surface-sized. 100% cotton watercolour paper lets the juice soak in rather than sitting on the surface, where it flakes. It is the same paper as in the cyanotype kits.
- A positive printed on transparency film. The same film as for digital negatives — only the polarity changes at printing, and you should aim for high contrast, since the process compresses tonality.
No Vision Picturale kit covers the anthotype, and that is consistent: there is no chemistry to formulate, hence nothing to reformulate. This process is the reference point for the whole catalogue. When we call a cyanotype or a gum print "non-toxic", the anthotype is the standard we measure ourselves against — the one process that never needed reformulating, because it never contained anything.
Tristan Sidem & Raphaël Lebas de Lacour — Vision Picturale
