The printing technique Cliche’ – verre is a curious rarity unknown even to most Art experts .
Perfected in 1839, simultaneously with the patent Daguerrotipia, comes from the discovery of the English scientist Henry Fox Talbot of what he calls “Charter Photogenic” or treated paper in order to become sensitive to light.
Talbot in fact, weighed down by his inability to draw the beautiful scenery of Lake Como visited on honeymoon, relentlessly tries to reproduce reality with a printing technique that would allow a positive run of multiple copies.
A few months later the brothers Havell engravers and their colleague James Tibbitts present to the world the first copies of “photogenic drawings” or cliche’ – verre .
These images are printed on photosensitive salt paper impressed by sunlight filtered through a negative obtained from a glass plate and drawn by hand .
The process is deceptively simple but revolutionary .
In the first place the glass plate must be blackened with a paint that does not allow the passage of light . The design must then be carved with a metal tip that will remove the black paint in places where you will want to impress the paper. It goes without saying that are not possible alterations or second thoughts.
The paper must be prepared by hand according to a recipe to allow long and repeated baths in water and harsh chemicals.
The sheets are then immersed in animal gelatin and, once dry , salted with a solution of ammonium chloride and sodium citrate .
Barely dry, the salted paper goes intothe difficult sensitization with silver nitrate in a dimly lit using a safety light green. Now the paper will react when exposed to ultraviolet rays that convert the halide Silver Silver stable metallic and blackened .
The silvering, however, tends to darken and the artist has a couple of hours of time to expose to the sun the paper well pressed under the graffiti glass.
From this moment on, the chemistry and the clock must give way to experience, taste and intuition. Or maybe to Fortuna.
It takes just the appearance of a cloud or the flight of a bird in the sky to drastically affect the color or tone of the press. Take a few seconds exposure, or a different angle of the sun to undermine any result.
The paper imprinted with the desired design you should wash long in the dark, revealing solfogallica in a solution that will change the color on a virtually unpredictable and may in another bathroom before the color change to gold salts and the final wash.
It will take at least ten days to see the final result.
It is a process in which the artist’s ongoing decisions directly affect the result, and that in no way lends itself to standardization criteria .
Photo printing on salted paper will in fact soon be abandoned in favor of more controllable and safe techniques .
But a small group of great artists fell in love with the method.
Camille Corot, Millet, Rousseau and Daubigny, Delacroix, and even wrestled with the new technique . The Barbizon school to complete entire summers devoted to the cliché – verre .
Later, with the disappearance of the salted paper and industrial production of the photosensitive papers cliché – verre a curiosity becomes more easy to perform but very little charm.
Paul Klee in 1902, Man Ray in ’17 , Picasso and Bruno Schultz with his Book of idolatrous ’22 show interest in a technique that inevitably goes extinct already hybrid technology.
I proposed a very limited edition of cliché – verre in salted paper knowing full well the huge amount of missed results of many hours of exciting work, the unpredictability of the sun and developing baths .
Each copy is profoundly different and will react differently over the years keeping the memory of when it has, literally, came to light .