Monthly Archives: Νοέμβριος 2009

Η συντήρηση της αίθουσας των κατόπτρων

Eργασίες συντήρησης της αίθουσας των κατόπτρων στις Βερσαλλίες.

Δείτε και τις παρακάτω φωτογραφίες:

http://www.lightmediation.net/blog/podcast/july/versailles_chateau.pdf

Πηγή: http://www.lightmediation.net/blog/index.php/category/world-heritage-patrimoine-mondial/france-patrimoine-mondial-world-heritage/

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How to Identify Graphic Art Prints

Intaglio

is an Italian word meaning to cut into. So intaglio prints are made from a

plate, usually copper or zinc, which has the image cut into it. These

prints are otherwise known as etchings, engravings, aquatints,

mezzotints, and dry points.

A print is made by inking the lines and depressed surface areas of a

plate, wiping the excess ink off of the surface, and using a press to

force the remaining ink onto the paper. The intaglio process has been used

since at least the 1400’s, when it was probably created as a means of

recording a pattern to be re-used for engraving into a precious metal

object. The earliest prints are German.

Engraving

A tool like a pointed chisel is used to cut a groove into the plate. This

groove will hold ink that will be transferred to the paper during the

printing process. As the feather edge turned up along the edge of the

groove by the tool will wear away quickly under the pressure of the press

an engraving is usually printed in small quantities.

Since it is necessary to actually cut into the metal plate while creating

the image, engravings are simple in construction, relying on a series of

parallel and cross-hatched lines. This formal technique is easily seen

through a magnifying glass.

Engraving has been used extensively from about 1700 – 1880.

Drypoint

A sharp point is used to scratch an image into the plate. This scratch is

sufficient to hold the ink during the printing process. These prints can

have a looser look than engravings since the artist does not need to be

precise as with a burin.

The line left by this method is best described as scratchy. It is rough

and irregular, just the way you would imagine a line would be which was

scratched into a metal plate. It may be possible to see a thick black line

with a thin white line running down its center. This is somewhat common

and is caused by the burr created by the drypoint in the metal plate

holding ink off to either side of the actual line.

This technique was popular during the late 19th Century, (1870 – 1900).

Etching

The metal plate is covered with an acid resisting material. The image is

then drawn with any appropriate tool that will cut through this layer of

acid resist down to the metal plate. The plate is then placed into an acid

bath that will eat away at the areas where the image has been drawn. This

produces the grooves that will hold the ink.

An etching will usually be much more free flowing in style than an

engraving since the artist can draw with any tool that will break the

surface of the acid resist rather than having to cut into the metal plate

itself. Where the lines in an etching might terminate in a sharp point

caused when the burin is slowly raised from the end of the groove, an

etching will have lines that are bluntly terminated. This is caused by the

equal action of the acid on all parts of the line.

Where lighter and heavier line strengths are required different areas of

the plate can be subjected to shorter or longer periods of immersion in

the acid bath. This is called ‘stopping out’.

Etchings have been made since about 1500, but regained popularity during

the last half of the 19th Century, (1870 – 1900).

Aquatints

A fine powder is sprinkled onto the plate and then baked into place. This

powder will resist the acid etching depending on its density and

composition. The texture of this powder, when dried onto the plate, is

somewhat like dried mud in the bottom of a pond, forming small islands

with uneven edges. These small islands have also been described as having

the appearance of black lace. The plate is placed into an acid bath where

the acid acts only on the areas left exposed around the islands of the

acid resist. Texture and density are determined by the time spent in the

acid bath, the size of the islands, and the area between the islands.

At a distance these prints will appear to be similar to watercolors, with

soft textures and hues. Close examination will reveal the small islands.

This technique was known earlier, but became popular about 1770 and

continued until about 1830.

Mezzotint

A number of specialized tools are used to poke tiny holes into, but not

through, the plate. Each of the tools has its own characteristics, but

generally the effect is to cover the entire plate with these tiny pock

marks. If the plate were to be printed when in this state it would print

entirely black. Burnishing out selected areas, effectively shrinking or

closing up some of the ink pockets creates the image.

These prints are the richest, darkest of the intaglio group. The over all

effect is unique, but you may also look for a series of small ink pockets

along an edge left by the tools used to create a mezzotint. A mezzotint is

not etched.

This technique was popular during the last half of the 18th Century, (1750

–1800).

Relief

prints are made by cutting away the areas around where the image will be.

Ink is then applied to these raised areas and then transferred to the

paper either manually or in a press. When printed manually the back of the

paper will often show the wear marks of the baren. This is a pad used to

apply pressure to the back of paper which has been placed face down onto

the inked printing block.

Relief prints are most often done in wood or linoleum. Wood engravings,

though similar in appearance to metal engravings, are also relief prints

since the area around the image is cut away leaving the raised area to be

inked.

The Japanese produced exceptional wood block prints during the period 1750

– 1850. Early German examples are dated from the 1500’s and represent some

of the finest graphic artwork known. Broad flat areas of solid color often

characterize Oriental woodblocks, while fine detail can be seen in the

German examples.

Wood Block (Linocut)

These prints are cut on the plank side of a piece of fine-grained

hardwood. Linocut uses the same technique, but is cut into a piece of

linoleum. These prints will usually have large areas, flat perspective,

and may incorporate the wood grain itself into the image. Each color in a

relief print will be cut from a separate block and individually printed.

The image area on a relief print will be slightly raised from the

background as the paper is embossed onto the raised inked areas during

printing. This technique can be used to white emboss areas of the print in

which the image was left intentionally without ink.

Wood Engraving

A very close grained wood is used along with typical engraving burins to

cut the outline of the image into the end grain of a block of wood. This

gives a much finer line than is possible in other block printing. The ink

remains on the surface of the image and so is classified a relief print.

These are very similar to engravings and often will require experience to

tell the difference. To visualize the difference between an intaglio

engraving and a wood engraving relief print, remember that where an

engraved image is constructed of a series of black lines built up into an

image, a wood engraving uses a series of white lines cut away from a black

image.

The wood engraving technique was developed around 1800 in England.

Planographic

prints are one of the newest techniques developed and the most plentiful.

These are generically lithograph prints. Within that category are stone

lithograph, chromolithographs, and process lithographs. All use the same

principle…water and oil do not mix. The lithographic technique was

discovered about 1800 in Germany.

Stone lithographs

A stone with a grain appropriate to the image desired is used. The image

is drawn on the stone, (or is transferred to the stone using a special

transfer paper), with a greasy pencil. The entire stone is then wet with

water, which is repelled by the greasy substance. Greasy ink is then

applied. This sticks to the image and not to the rest of the stone which

has been wet with water. The image is then printed.

Depending on the texture of the stone and the type of drawing tool used,

the image may appear to be coarse or fine. Backgrounds can be entirely

filled in or left blank. The ink will lie flat on the surface and the

paper will also be flat, with no raised or incised areas showing pressure

points.

Chromolithographs

These are stone lithographs, but instead of printing large areas of a

single solid color, the artist will use a coarser stone and print one

color on top of another, through as many as 60 stones, to achieve the

particular color, tone, and shade desired. This technique produces very

vibrant colors.

Examination through a magnifying glass will reveal small ‘dots’ of color.

Each dot is individual and unique. Do not confuse these dots with those

formed by a process lithography technique explained next.

Chromolithographs were very popular from about 1860 – 1910.

Process lithography

This technique covers the group best known today. Almost all commercial

printing uses process lithography. These prints are made mechanically. A

photographic image is made. A ‘screen’ is made from this photographic

image. The screen will actually have holes in it that will hold the ink.

The size, shape, and spacing of the holes will determine the image

tonality. The screen is inked and the image transferred to a rubber roller

from which it is then transferred to the paper. (Thus the term ‘offset’

printing).

This technique is easily recognizable in color prints. The colors are

formed from a pattern of dots. Each dot within the pattern is usually of 1

of 3 or 4 colors. (Thus 3 or 4 color process). The combination of these

colors in the intensity printed forms the overall color of the print. Look

for the dot pattern with a magnifying glass on better prints. Newspaper

printing uses the same technique and is easier to see, so practice there

first to recognize the dot pattern. It will usually be a circular pattern

formed by 3 – 4 dots of distinct color.

This technique has been popular since about 1920.

Screen and Stencil

prints are printed using a mask. Portions of a stencil or screen are

masked off to prevent the flow of ink passing through. The open areas are

printed. Several stencils or screens are required to make an image. These

may be recognized by their broad areas of color, occasionally overlapping

color areas, and sometimes a silk screen impression will retain

impressions of the screen in open areas of the print.

While hand coloring of existing prints by use of stencils has been around

since the very earliest days of printing, silk screen printing is a

product of this century.

Bibliography

Ivins, William M. Jr, ‘How Prints Look’, Beacon Press, Copyright

1948

Gascoigne, Bamber, ‘How to Identify Prints’, Thames and Hudson,

Copyright 1986

Kanada, Margaret Miller, ‘Color Woodblock Printmaking’,

Shufunotomo Co, Copyright 1989

Ross, John, et al., ‘The Complete Printmaker’, the Free Press,

Copyright 1972

http://hubpages.com/hub/How_to_Identify_Prints

 


conservation bookbinding

Bookbinding: Minimal Intervention on 3 books

Codicology: the history of the structural features of the Codex Sinaiticus «Flavio Marzo»

What is Codex Sinaiticus?

Codex Sinaiticus, a manuscript of the Christian Bible written in the middle of the fourth century, contains the earliest complete copy of the Christian New Testament. The hand-written text is in Greek. The New Testament appears in the original vernacular language (koine) and the Old Testament in the version, known as the Septuagint, that was adopted by early Greek-speaking Christians. In the Codex, the text of both the Septuagint and the New Testament has been heavily annotated by a series of early correctors.

The significance of Codex Sinaiticus for the reconstruction of the Christian Bible’s original text, the history of the Bible and the history of Western book-making is immense.

Για να δείτε τις εργασίες συντήρησης του κώδικα πατήστε τον παρακάτω σύνδεσμο:

http://codexsinaiticus.org/en/project/conservation_codicology.aspx

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