Serigraphs or silkscreen are the same.An ancient methode of oriental printmaking which, considerably modified and ameliorated, has become one of the foumost important methods printing.Contemporary artists have made much use of it as a printmakig technique. The principle of screenprinting consists in applying stencils to screen (constructed of silk or of some synthetic or metallic material), in such a way that when ink is applied it is prevented from passing through some part while penetrating the rest of the screen, thereby printing an image on paper placed underneath.The screen is stretched across a frame and attached to a base in such a way that it can readily move up and down, so that paper can be easily placed and removed as required. For each impression, the paper is placed against registration tabs to ensure the printing is done in the correct position. The ink is poured over the masking at one end of the screen and when this has been lowered into position, the ink is scraped across the screen with the aid of a squeegee. The most important part of the process is the preparation on the screens.A drawing can be made directly on the surface with a special ink which is removed in readiness for printing after the rest of the screen has been blocked out. A photographic stencil is made by initially sensitizing the screen.
Lithography: With woodcutting and intaglio engraving, this is one of the oldest methods of pritmaking. It dates from the end of the eighteenth century.The design is drawn or painted on the polished, or grained, flat surface of the stone, ususally Bavarian limestone, with a greasy crayon or ink. The design is chemically fixed on the stone with a weak solution of acid and gum arabic. In priting, the stone is flooded with water which is absorbedeverywhere except where repeled by the greasy ink. Oilbased printer"s ink is then rolled on the stone, which is repelled in turn by the water soaked areas and accepted only by the drawn design. A piece of paper is laid on the stone and it is run through the press with light pressure, the final print showing neither a raised nor embossed quality but lying entirely on the surface of the paper. The design may be divided among several stones, properly registered, to produce, through multiple printings, a lithograph in more than one color.
Etching: Lines are bitten into the metal plate through the use of acid. To begin with, the plate is covered with a thin, acid-impervious coating called a ground which is smoked to a uniform black. Lines are drawn through the ground with a stylus baring the metal of the plate. Acid is then applied which eats into the exposed areas. The longer the plate is exposed to the acid, the deeper the bite and therefore the stronger the line. Different depths are achieved by covering some lines with acid-impervious varnish (stop-out) and biting others a second (or third) time. The appearance of etchings is usually free and spontaneous but the technique has occasionally been used to produce results almost as formal as engraving.
Aquatint: A technique of acid-biting areas of tone rather than lines. A ground is used that is not completely impervious to acid, and a pebbly or granular texture (broad or fine) is produced on the metal plate. Stop-out and second and third bitings are.used to produce variations of darkness.
Giclee: A giclee (zhee-CLAY) is an individually produced, high-resolution, high-fidelity reproduction done on a special large format printer. Giclees are produced from digital scans of existing artwork. Also, since many artists now produce only digital art, there is no "original" that can be hung on a wall. Giclees solve that problem, while creating a whole new vibrant medium for art. Giclees can be printed on any number of media, from canvas to watercolor paper to transparent acetates. Giclees are superior to traditional lithography in several ways. The colors are brighter, last longer, and are so high-resolution that they are virtually continuous tone, rather than tiny dots. The range, or "gamut" of color for giclees is far beyond that of lithography. Lithography uses tiny dots of four colors–cyan, magenta, yellow and black–to fool the eye into seeing various hues and shades. Colors are "created" by printing different size dots of these four colors.Giclees use inkjet technology, but far more sophisticated than your desktop printer. The process employs six colors–light cyan, cyan, light magenta, magenta, yellow and black–of lightfast inks and finer, more numerous, and replaceable printheads resulting in a wider color gamut, and the ability to use various media to print on. The ink is sprayed onto the page, actually mixing the inks on the page to create true colors.They are priced midway between original art and regular limited edition lithographs. Limited edition litho prints are usually produced in editions of 500-1000 or more, but giclees rarely exceed 50-100 reproductions.Giclees were originally developed as a proofing system for lithograph printing presses, but it became apparent that the presses were having a hard time matching the quality and color of the giclee proofs. They evolved into the new darlings of the art world. They are coveted by collectors, and desired by galleries because they don't have to be produced in huge quantities with their large layout of capital and storage.