Page 201 - Art-Addiction

may also be prepared manually, PHotoLItHoGraPHy stored and conserved. “).
as in the cliche-verre, a process A term referring to the use of PosItIVe & NeGatIVe PrICKING
which could be classed among photography in lithography and Photographic terminology is A method of transferring a
the printmaking techniques. offset lithography. sometimes applied to prints; drawing, which consists in
Photomechanical processes PH VaLUe i.e. a positive design is black on pricking with a fine needle the
are those which involve a com- P(otential) of H(ydrogen). A white, a negative one is outlines of the design, leaving
bination of photography with method of measuring acidity white on black. a series of small holes which
traditional printmaking meth- or alkalinity, numerically “PoUPee a La” may then be pounced. This
ods; a positive or a negative equivalent to 7 for neutral solu- The French term used for a involves shaking powdered red
image can be reproduced on tions, increasing with increased method of coloring an intaglio chalk over the dots so that a
the surface of any metal plate, alkalinity and decreasing with plate by hand. Contrary to usual trace of the design is obtained
stone, wood block or screen, increased acidity. The pH scale methods of color printing, the on the paper or plate placed
provided that it has been sen- commonly in use ranges from different colours are all applied underneath. The process was
sitized beforehand. examples 0 to 14. on one plate with the aid of much used in lithography for
of photomechanical processes PIGMeNt a stump of rag, known as a transferring drawings.
are: line block, halftone block, The constituent in ink which “poupee” (or dolly). PrINt
photogravure, collotype, and gives it color PreParatory draWING The image obtained from any
such techniques can also PIttING Before making an engraving, printing element. Originally,
be applied to screenprinting A fault which occurs on metal woodcut, etc., a preparatory this was either a metal plate,
and offset lithography. The plates, particularly aluminium. drawing is made on the surface engraved in intaglio, or a wood
artist can also make an image small holes are also sometimes of the printing element. It may block (or metal plate) cut in
by combining photographic found on the rubber roller used be a tracing or transfer of the relief. From the beginning
materials (i.e. sensitized paper, in offset lithography. An etching original design, or it may be an of the nineteenth century,
developer, fixative, etc.) in his ground may also be pitted original itself, done with pencil, lithographic stones were
own fashion. For a long time, with small holes caused by an ink, chalk or other medium. included, and today screen-
photomechanical means were excess of heat on application of Press, PrINtING printing adds a further type of
rejected in the definition of the ground. The three most important printing element. An impression
original printmaking, for it was PLaster Cast types of press are: (1) the relief taken planographically from a
not considered to be work done A type of trial proof taken or typographic press; (2) the painted surface may also be
entirely by the artist’s hand. from an intaglio plate. Plaster intaglio printing press, also termed a print (see:monotype).
This restriction is no longer is poured over the plate after used in photogravure; and (3) In the past, a rigid distinction
regarded as valid, for it is now it has been blackened with the planographic press used in was observed between prints
appreciated that the artist may smoke, thereby producing an lithography and offset lithogra- obtained by manual processes
use any photographic means exact mould of the design. phy. Within each of these types, and reproductions obtained
at his disposal in the making PLastIC (engrAVIng On) the manual press is generally by photomechanical methods
of a print. sheets of plastic can be used by artists making their (see: photographic processes).
PHotoGraVUre engraved in the same tech- own prints, and can be distin- This distinction has less value
sometimes known as helio- nique as a woodcut or wood guished from the mechanical today, because reproductions
gravure (particularly hand engraving. The transparency of press used in industry. have been incorporated into
photogravure), this technique the material greatly facilitates 1. In the relief press (see: let- artists’ original prints and are
is one of the most important registration in color printing. terpress), a heavy rectangular therefore not solely produced,
methods of industrial printing PLate element, the platen, is lowered as originally intended, for
(the others being letterpress The plate is any metal printing over the bed of the press onto mass production. A print is
and offset lithography). It is an element, whether an intaglio, the paper and the block. termed, “original” if the artist
intaglio process which can be relief or planographic process is 2. An intaglio printing press is of the design has worked on
divided into two procedures: employed. comprised of two cylinders, the printing element himself,
(1) Hand photogravure, a PLate MarK between which the paper and as opposed to reproductive
derivation of the aquatint in The mark imprinted by an the plate are pulled under great and interpretative prints which
its method of obtaining tone. intaglio plate onto the paper pressure. involve the use of an inter-
After sensitizing a copper plate (especially visible at the edges) 3. In the lithographic press, mediary person to reproduce
and exposing it to light to form caused by the pressure of the the stone and the paper are the design onto the printing
the image, resin or bitumen rollers in the press. transported by a mobile bed to element. Original prints are
grain was scattered over it. The PLUG a position beneath the scraper often only produced in small
procedure continued as for A small piece of wood (or lino- which supplies the pressure. numbers; they may be num-
a normal aquatint plate. This leum for a linocut) known as a There are different models of bered and signed by the artist.
technique subsequently devel- “plug” is inserted into the block each type of press; they vary These distinctions between
oped into a totally photome- as a means of replacing a bad according to the manufacturer reproductions (which occasion-
chanical process: (2) Machine error or a damaged area in a and the period in which they ally may also be signed and
photogravure, in which the woodcut. It is cut in accordance were made. numbered) and original prints
tone is supplied by a cross-line with the correction or restora- PressUre are, however, generalized.
screen. It was discovered that tion to be made. The pressure of an intaglio In practice the frontiers are
the plate could be bent into the PoCHoIr plate on the paper when pulled more imprecise, particularly in
form of a cylinder, a develop- stencil cut, coloration. through the press results in the commercial printing. It must be
ment which allowed very fast PortfoLIo formation of a plate mark. In noted that some people have a
printing speeds (rotogravure). A pliable case, made of thick French, a distinction is made much more rigorous definition
The technique is used more for cardboard, frequently covered between the plate mark on the of an original print than others,
magazines and catalogues than with leather or cloth, in which recto of the paper (“cuvette”) e.g. of a photomechanically
for print-making itself. prints are presented, and that on the verso (“foulage produced original print of which
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