The basis for most methods of photolithography is copying photographic negatives or slides with light on the stone (or metal plate), the prepared chrome colloid. The essence of this is to copy that chromic salts of potassium and ammonium in conjunction with such substances (colloids) as a carpenter's glue, gum arabic, albumen (egg white), and others, have a sensitivity to light. By light they zadublyayutsya and lose the ability to dissolve in water. If you put on a stone (or metal plate) thin chrome albumin, glue or gum arabic, to subject it to light through a photographic negative and the roll carbon paint, the paint by washing with water to hold out just lit areas and unlit places the layer of solution and will go along with paint. As in zincography, produced from the original artist first photographic negative.
If the picture was taken of the artist in black ink pen or solid spots, without blur - manufactured dashed negative, then there is one on which all the streaks or spots will be equally clear on the general dark, opaque background.

If the figure of the artist has been made in ink or watercolor vrazmyvku shading or lead pencil on smooth paper (that is, when the figure has different strengths tone) - made bitmap negative.

This film is obtained by shooting through a special optical device - a "raster" (grid). Raster is a glass or transparent plastic to put on them with black, opaque lines (a grid) and the transparent gaps between them. Drawing on the negative when shooting through a broken screen turns on the smallest number of opaque and transparent dots of different sizes and at different distances from each other. Number of these points varies from 400 to 3600 (and even more) for every square centimeter of the negative, depending on the survey taken at the raster. Top-selling pattern for photolithography are: works for a large scale (large posters, flyers, etc.) in large quantities and poor quality paper rasters taken in 2030 lines per inch (then in each square centimeter of the negative, and therefore, and Reproduction will be from 20x20=400 30x30 = 900 points) for works knizhnozhurnalnogo type (children's books, covers, calendar blocks, etc.) are taken raster lines in 3048 (then in a square centimeter of the points will be 30x30 = 900 48x48 = 2304 ) for more precise work with gentle transitions tone (reproductions of paintings, inserts in expensive editions, portraits, etc.) are printed on high quality paper, bitmaps take from 48 to 60 lines (while in a square centimeter of the points will be 48x48 = 60x60 = 2304 to 3600).

The resulting bar or raster film is copied to a blank stone coated (velvet or tampons in a special centrifuge) photosensitive layer consisting of egg white (albumin) and ammonium dichromate, dissolved in water.

Dove layer to dry on the stone put tape down the bar or raster film and placed in a special copy machine, where the film is pressed against the stone. Light white light will pass through the transparent streaks, spots or points of negativity, a photosensitive layer on a rock in these parts harden and lose its ability to dissolve in water. Through an opaque background or through opaque pixels negative light on the stone will not fall, and the light-sensitive layer at these locations will retain its ability to dissolve in water.

After finishing up the stone along with the negative is removed from the copier machine, transferred to the laboratory with a yellow safelight light, remove the negative, and the stone is rolled completely thin layer of special carbon paint (like a fat transfer ink), diluted with turpentine.

After that, a stone is placed under running water and gently rubbed with a piece of wet sponge. Unlit chrome layer of albumin together with the paint away with a stone and it will remain only strokes, stains or drawing point where the light-sensitive layer is dry, so the paint on it endure.

Dried stone further processed as a normal transfer.

When color photolithography, as well as in zincography, from color separations are made of original negatives for each color. These negatives are copied to the stone as well as in the one-color lithography.

Instead of negatives and positives can use a transparent film grain on which the image is applied with black paint. After that, the film emulsion side to have sensitized colloidal layer on the stone, pressed and exposed. Then the process goes in this order, as described above.