. . . . . "Sensitive sheet after exposure" . "1790543979"^^ . "1790403662"^^ . "Dichromated sheet removed from the camera after one full day of exposure. The trace of the sun is visible as an arc across the sheet.\n\nThe faint negative image is turned into a positive after the dichromate (yellow stain) is washed off and the gelatin substrate that was holding it is soaked in water until it swells. The dichromate hardened the gelatin where it was exposed to light, the more so in the highlight areas. \n\nAfter swelling, the gelatin is dusted with a very fine powder made of resin and pigment (lamp black in this case). The shadow areas, which have been hardened less by the dichromate and have swollen more than the highlights, will retain more of the pigment, and will trap it when they dry, thus giving a positive image." . . . . . "SoFiET/SoFiET-VI/7LZQomf222jwYj9D" .