THE CROATIAN ACADEMY OF TECHNICAL SCIENCES

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Nov 29, 2013 (3 years and 11 months ago)

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THE CROATIAN ACADEMY OF TECHNICAL SCIENCES

THE ZAGREB UNIVERSITY


dr. Vilko Žiljak

PROFESSOR ON FACULTY OF GRAPHIC ARTS


GRAPHIC ENGINEERING AND DIGITAL PRINTING


PREAMBLE

Ten years ago our country was the first to have the courage to incorporate digital
color images into all documents. It is impossible to “unstick”, replace or forge such
non
-
material images. Today almost all the countries in the world use digital
processing of document information. Except for a rather good know
-
how a decade
ago, our newly

formed state did not have any technique for making documents. Our
country was at war then, isolated, a state not yet recognized by the world. Highly
qualified graphical engineering could be found only here
-

in Zagreb. In such
circumstances when everythin
g was done with a fresh start, graphical experts had
the opportunity to skip the conventional printing methods and to produce documents
digitally. It was also then that our money was among the first in the world to be made
and designed as computer graphics
. The cartography was made digitally in a
completely new manner, because all the analogous originals are still abroad. This
was an encouragement to give more space to digital technologies in printing. Since
then hundreds of engineers have completed such mo
dern studies of printing and
they have been implementing digital techniques into practice, i.e. the prepress,
design, reproduction photography, printing, finishings, and other final processing.


1. INTRADUCTION

Digital printing development is correlated to

computer innovations. Computers have
been introduced into graphical and printing systems only when speed and memory
capacity were sufficient to process texts and pictures. The memory capacity of a
standard color monograph is 10 gigabits. If our intention
is to print such a book in one
hour, then the other computer parameters are set: the computer speed, printing
speed, computer memory, the printer memory and the speed of data transmission in
the network between the computer and printer.

Each new computer d
evelopment introduced improvements into printing as well.
Computers make it necessary to integrate systems in the graphical industry: A
prepress system, printing system, postpress final processing, graphical preparation.
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There is a demand for production to

become more fruitful, more flexible and
transparent. There is also demand to shorten the preparation time in all printing
phases and to constantly enter into more and more complicated jobs. A fully
automatic work process is being introduced. This makes it

possible to have the
complete job automatically led, beginning from the moment of order placement,
purchase and up to the moment when the final product has been produced. This
requires co
-
operation between the seller, printer and buyer in various fields.


A special problem is the one how to integrate machines made by different
producers. It is necessary to create a Graphics Language, a communication
language. XML has found itself in the middle of these strivings.

Now, at the beginning of the 21st century,
digital printing is being applied widely.
During the previous decade digital printing was successful in the black
-
and
-
white
technique. Color digital printing was present only in certain fields: small runs and
individual prints. Graphical engineers in Croat
ia applied digital printing in all
development phases development. We were among the first in the world to have first
-
class color digital printing. The same may be said of the training that graphical
experts got on all levels.


2. CHANGES IN PRINTING INDU
STRY

In printing there has been great changes: new methods of graphic typography have
totally pushed out methods and techniques that were used up till ten years ago, now
it is happening in the press which is pulling out the automation in processes of
bindi
ng and finishing. In the same time symbiosis is emerging in new and traditional
techniques of printing, the are replenish combining. Strong development of
computing relates to the development, changes and new methods in printing. This
year a few congresses

were taking place, seminars, professional and scientific
meeting, as well as the colloquium about new patents in digital printing. Serious
discussions were on the issues of fundamental postulates of graphic production.
There is a new way to try to analyse
, understand and discuss science of colours, the
methods of hybrid systems of electronic printing.


Graphic structure and printing was for centuries closed exclusively for specialised
activity and schooling of a high manufacture skill. Till the moment of c
omputer usage
in graphic production, nothing significantly different has not happen till the
Guthenber´s time, although during this five centuries numerous patents were offered.
Small steps in graphic techniques were made by the end of the last century by
means of offset and machine type setting. Crucial step of changes starts with the
computers of eighties of this century. Along with computers there disappears forever
many graphic techniques used so far, as well as methods and ways of production.
Education

has been changed, the old nomenclature of walks of life have been
abandoned, new relations between publishers, printers and authors have been
arranged.

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Printing was during centuries making its own tradition, reliability and stable
methods in production an
d skills. Along with computers all the methods of typesetting
to reproduction photography perished. With computers a page layout is solved,
corrections, colour separation, proof printing, transferring text and images to log
distances, making a printing pla
te, mining all prepress procedures, and now
computers are inside area of printing by which an end has begun for many traditional
techniques in printing industry.

Our generation is lucky to be a part of this important historic fracture, to be included
in
a number of developing and researching chapters that cover fundamental physical
-

electronic researches, hardware development and software in visual
communications and a research in the field of colour
-

perceiving. The main reason of
computer usage in pri
nting was started by mathematicians who found in graphic
endless new domain for researches. Usually we put this results into the chapters of
“computer graphics”. Products of this researches we experience in unbelievably
visual usage from the image for prin
ting to the animation and digital moving picture.
Physics and electro
-
chemistry were left many open questions from the field of
electrophotography, magnetography, viscosity of liquid toners, drying and deep
-
heating toners, penetration of pigments to differ
ent materials.

2. 1. Changes with computers

The results, by entering of the computers in graphic printing, are astonishing not on
the field of competition yesterdays graphic methods and techniques, but on the offer
of solving new products and extension tho
se printing fields which were, using the old
techniques in the middle of nowhere.

News, results, changes and consequences of computer application?

-

the explosion of colour printing on all publications;

-

a number of new mathematic raster shapes in speci
alised applications;

-

digital halftoning on the level of separate image element;

-

stohastic rasters with the ability of multiseparation and combined hybrid rasters
solution;

-

spot separations in tens colour shades;

-

colour usage in daily press (which h
old greater part of the graphic reproduction
and were always an imperative for printing development) with managing and
optimization of colour spending on the level of a pixel;

-

highly improved quality in printing magazines, based on digital scanning, com
puter
image processing, and usage of digital photocameras;

-

the development of GCR, UCR and UCA methods in colour separations;

-

optimization in colour and material spending, as well as in exploitation of
equipment depending on the edition, usage and qua
lity;

-

individualization of image print, by means of a number and a code in long runs;

-

programming binding, folding, automation in finishing;

-

created digital printing integrated with conventional printing in hybrid and modular
graphic systems;

-

the
ability of connecting the printed material and products with information system
for the control and warehousing the goods;

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-

introducing CDs and DVDs as the main electronic warehouse of all interphases in
graphic production.

New computerised printing enab
les the author and a graphic worker to see, lead
and control the complete graphic process from typesetting to printing.

From the middle of eighties we have extraordinary growth of researches and
development of computer interfaces in printing industry. Rich

diversity of
technological processes, direction
-

based on new relations of pixel, raster, colours
and material for printing, has opened a big interest in the research and experimenting
which gave more significant results and has changed many relations in

graphic
profession. There have been opened new applications, so from the paper graphic
methods moved over to computer systems, video, animation, drawings and combined
techniques where dominate multimedia solutions. Computer systems allow
interactive conve
rsions and using the same issue for realisation in different media.
Ideas started in graphics can be stretched to video, film, three
-
dimensional solution
and turn back to be improved by a number of iterations, to work out or change the
starting conception.

These technologies integrate different media and link different
know
-
alls.

Monitor layout of information is the future and the greatest step forward of the
graphic profession. This development is in symbiosis with publishing and graphic
prepress. Al
l publications prepared for printing have their own electronic presentation.
Paper and printing industry has its future in digital printing with new solutions of
graphic design. If computer graphics did not interfere in graphic engineering,
probably, print
ing would already be at the end. The look of today printing material
thanks only to computer technique which did not only get back, but did also
increased the interest of taking over the informations through printing products and
an interest for this profe
ssion.

2.2. Changes in education of graphic engineers

Computers broke the exclusiveness of graphic skills for a small number of printing
workers. We have changed the programs of learning the printing and offered the
ability of continuous adjusting lecturin
g by new technological experiences. The price
of the graphic prepress equipment (which by production manners could hardly be
compared to those from new printing era
-

consider only fifteen years), is decreased
hundred times. This has pulled out the graphic

prepress from printing sections to the
desk of the author, journalist and editor, and entered to primary education. “Desktop
Publishing” was created. Graphic image and text processing is nowadays prepared
under a hand of an expert from almost all profess
ions, and a direct link to this kind of
format and printing machine has opened to authors and publishers a new interest in
publishing on a paper. Traditional methods of printing include typesetting, image
rasterizing, making a printing plate, print and bin
ding. Computer technology has
differently ordered these titles, so new professions has emerged, as well as new
approach to education. New terminology was created, new procedures of production
so this invoked a new demand for basic knowledge supplement, the

need for new
engineers. Now, graphic prepress employees more workers than before because
market wants more complex solutions, attractive, interesting in design which is
possible to achieve by today software and hardware, which couldn’t have been
realised
by means of former techniques.

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Computers and automation have changed a structure of employees of the
assortment of a graphic product. A few years ago printing was overloaded with
several hundreds titles in the profession nomenclature. A graphic product was

produced in separated steps and each kind of a production process was asking for
different education degree and different qualifications. Today all skills; from typesetter
to the repro
-
photographer and partially a printer
-

they are all in the same room.
That
happened in a process of production. Many job flows were optimized as well as
working tasks and working places. Production of a graphic product nowadays is only
passible if conducted by a hand of one person which manages and operates a
printing machin
e by means of a computer all the way from the idea to the graphic
prepress procedures. This is why it is hard to distinguish a border line between the
prepress and printing and intersteps in today printing era. There has emerged a
modular printing house; w
here for a certain product utility link of machines is set, and
production procedures as well. By this, printing houses are less specialised for a
particular group of products or for tight aiming market.

A system of lecturing printing was meant to be chang
ed, in the forma that a printer
as single unit controls all the know
-
how of reprophotography, computer application,
digital printing and all the way to finishing the graphic product. Re
-
qualification here
does not mean abandoning old graphic skills, but it

by means of extending the
knowledge, it means entering safer business and professional life.

Adjusting the machine schedule to the aiming printing task opens the door to
dynamic printing house which seeks for workers with wider knowledge by nonstop
learn
ing, flexible people which will not allow to be putted in a whatever drawer of the
profession nomenclature. Printing industry, similar event happened to informatics and
computer application, is entering to global education into the title we have popularly
called “computer literacy”. A program of graphic education is extending to many
different media and thus giving a chance to all of us to estimate our future orientation.
Only, for this area it is hard to find good teachers currently active in refreshing th
eir
personal knowledge.

In professional graphic studies and schools there have been introduced attractive
subjects; design, ecology, computing, informatics. Their stronger extension takes
over hours that should be give to subjects that would process meth
ods and basics of
digital printing not excluding the subjects of conventional printing techniques. With
digital systems into graphics there enter new people, mostly younger wanting to be
included in digital printing industry.

A computer is highly tempting
tool and effect of that is that in graphic profession
there has been less interest in learning conventional printing techniques. Young
people want to be educated only in the direction of new attractive technologies. Soon
we shall have less experts in jobs
of managing current printing houses and installed
departments which will, still, be the most important in book production, of newspapers
particularly in processes of packaging.




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3. DIGITAL PRINTING

Conventional printing industry was perfect in th
e quality of eighties and emergence
of the digital printing technique in this years was not in the most lucky time and had
merely have any chance. Nevertheless, in the last decade of this century we are
witnesses that digital printing is successfully solvi
ng: high resolution, clean printing
surfaces, stable quality, density high key shades, similarity to the original. The
development moved towards a few directions, more important one are: with liquid
colours (ink jet), dry (deep heated) colours (electrogra
phy, ionography,
magnetography). Between this technologies there is no competition, they are fulfilling
each other, they all have found their field of application in the area of former graphic
products and have also largely extended the assortment. As far
as the speed is
concerned, magnetogrphy has those characteristics of speed that has an offset
printing, the development of magnetography each day gives new patents and for now
the only failure is existence only black pigment.

3. 1. Sequential printing

Clas
sifications of digital printing techniques: according to the colour transfer to
paper (impact / non
-
impact), according to the force of pressing the plate against the
paper, the rest classifications are related to the usage; number of printing units,
speed,

adjusting the edition, formats, principles of inputting a paper. With digital
printing there emerged another classification: according to certain printing plate.
Conventional printing reproduces equal prints, while digital printing brings a
sequential pri
nting and individualization based on variable printing plate. For
example, a book can be printed in a sequences from the first to the last page.
Printing plate depends on the memory size of the computer and not on the size of a
cylinder of the printing mac
hine.

Digital printing, just because it does not have a physical printing plate, allows each
point to be different from the one before according to the content and size. This has
opened some new possibilities of managing the printshop and processes of
pro
duction. It is allow that during the printing of some editions on the same machine a
printing of the totally different shape interferes not interrupting the continuing of the
first serial. The same machine is used for multiple proofs what guarantees that
a
pproved proof will be the same as print of the edition which is totally new event on
the way of highly qualitative finished edition. The proof on the final printing machine
managed from the computer used for the prepress phase, jumping over a few
tradition
al operations and the most important is to exclude the physically printing
plate with which we reduce the time of making the first approved print to continue the
printing of edition.

3. 2. Speed of the printing

Digital techniques in printing industry are a
t the beginning and complaining of the
traditions were regarding the speed of the printing comparing it to a conventional
printing in the amount in square meters of the printed material in the measure unit of
time. “Speed of the digital printing” includes:

computer efficiency, rasterizing, bit
-
mapping a print itself. There had been some talks about the digital printing as the
printing of small editions because there it had an advance. But complains to the
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quality vanished quickly, to the paper assortment an
d other material, like colour
stability. Square measure of the print in a unite of time is double each year
-

exponential increasing, so current digital colour printing has reached the speeds of
printing machines that were ten years ago (concerning the pri
ces and production
expands applied to long runs) while in conventional printing industry only a few
improvements have been made. The parameter of printing speed is literary in relation
with the development of computer technology. New printing patents in di
gital graphic
would be more numerous if the computer development was faster. Only the speed of
the development of computers defines new digital systems in printing. This
determined the speed of printing and indirectly it determined the speed of application

and changing of digital printing.

3. 3. Hybrid printing house

So far printing techniques, let us call them “conventional”, no matter the
automation, control of colour amount and system “computer to plate”, did not have
revolutionary movements. Speed, econ
omy and efficiency of printing traditional
printing, in last twenty years, increased only a few. Soon we will meet equalizing
economy of conventional printing and digital printing on long run and the
development of digital printing continues.

This is the r
eason of new perspectives to all activities in the process of printing,
marketing and organisation of production. When the connection of this digital and i
conventional printing abilities on the same material emerges, we talk about hybrid
printing machiner
y.

Digital printing today takes minor part in the entire printing production. About the
development and emergence of it we have experiences only from the last decade of
the 20th century. As invented in other novelties in conservative printing, printing
-
hou
ses did not run into the digital world. Conservativeness of printing houses could
not express the thrilling towards new technological spirit. Statistics say that digital
printing machines are installed in working printing house only in one fourth of them,
and the other three fourths are bought by the organisations with highly developed
graphic prepress; offices and copy offices orientated to the marked of small editions.
On this digital machines only a product is printed or only one phase of printing which
is not to be printed by a conventional printing techniques (offset, letter
-
press, flexo
-
printing) and these are mostly, highly qualitative small series mostly used for
marketing activities and competitions.


The concept of hybrid printing needs a cooperat
ion of old and new knowledge.
The development in graphic industry move si the direction of existing in many small
companies which are specialised, which cooperate. Cooperation is able only when
cooperants and end users now all other processes like printing
, repro, typesetting,
binding and other languages: language of the film, language of printing, language of
the media. Digital industry forces graphic workers to be open, but to be specialised
on the vertical.

3. 4. Stronger connections with the publisher

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New computer techniques have lowered the need for warehousing printed
samples. Print can be repeated by the request in the edition determined by the
market. By this we go deeper into the changes in the publishing activities. Relations
are being changed: pu
blisher
-

author, publisher
-

printing house, and new relations
are being set author
-

printing house. Machinery of financing the publishing projects
are being changed, we are dealing with copyright. Multiple edition is new as well as
the refunds of the edi
tion by the request of the market. Keeping the original, editing
the electronic printing plate, and emergence of the “electronic publishing”
-

is treated
in the new way over the data banks and modern techniques of searching the image
data. Computers enabl
ed “author manuscript” to look like the end product but printed
only in a small number of pieces.

Graphic prepress on the computer is good raw material for production of e
-
publication on a CD. If already mentioned monographic publication for printing had
ten GB on the paper presented on the monitor this e
-
publication will take approx. 50
MB.

3. 5. Pixel resolution and vector graphic

The point of digital printing is in connecting the computers with printing devices,
sending the information in textual an
d i image form from the computer to print in a
way to bypass the procedures of making the printing plate and a printing plate itself. If
we want to define what is a printing plate in the digital printing, it would be a memory
of a computer and technologica
l procedure of electronic printing. Because there are a
few directions in the digital printing development, the solutions of rasterizing is that
kind, from the same originals of information a files on a graphic page, a print of the
same quality is realised
. That what is printed, is saved in the memory in a form of a
pixel
-

image elements
-

of the enough resolution satisfying the criteria of quality of
our human eye perception abilities. Making pixels in printing is done in parallel rows
during the paper fl
ows calculated just before the printing starts. This event could have
been developed only when fast memories were developed and fast electronic
communications which consider the competition on the field of edition in conventional
printing. Pixelating in th
e act of printing is calculated from pixelization of images and
vectorisation of the text which are independent by size, density and direction of
image and text orientation, and are in the computer of the operator or the author of
graphic page. Pixel as a
term was created in the digital reprophotography, extended
many branches of computer application and has different meanings depending on
whether the pixel is observed in the process of scanning, image editing,
compression, rasetrizing, electronic printing

or unmaterial layout of the graphic page
on the monitor. A pixel can be one, two, three, four, even five and six bits (binary
colour amount)
-

in digital printing or 32 bits as it was at the beginning of the graphic
prepress
-

in scanning. In the descript
ion of the graphic page at the same time there
been printed two mathematic figures. Vector and pixel graphic; the first one describes
(mostly Bezier) the way of drawing the object and second which a surface to be
printed makes from independently settled in
formations in a colour shade of an image
element.

3. 6. Programming colours and new technologies

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Success of each image colour system demands relating methods of presentation,
control, managing the separation, gauging the device and an attempt to
standardiz
ation of the entire process. The most intensive discussions on this years
scientific meetings of printing are related to the suggestions of standardization of
colour management. There is a huge will in producing the unique system of flow of
the informatio
ns on colour independently of the devices. Each report begins with
“final discovery” of the system independent to the technologies of printing, and yet
they finish with promises that insufficiencies in suggested solutions will soon be
corrected. Standardiz
ation is simply not possible because the development of digital
printing digital today and the development of physical and chemical processes are
still in full speed.

Each day new discoveries are announced in toner technology, different physical
chemical
interactions of multicolour toner transfer, optical features of transparency,
reflection and light absorption. News in organic pigments and their photoconductive
features. Specific group of titles of our researches relates to the liquid pigments and
to dig
ital printing technologies which are using standard offset colours. Here we talk
about new physical processes of colour application and cleaning cylinders that make
the same relations towards printing as we have today in the offset. Determination to
studie
s of this technologies are right, because they lean to existing printing
procedures and printing machines with reasonable remakes. With strong arguments
these researches attach the development of digital pigments in electrography and
magnetogrphy which are

always expensive.

3. 7. Distributed production

Input information enters the direct printing from computers located beside the
printing unit or on the distant location. There are combinations, let us call it distributed
prepress, so a part of

images or pages is prepared at one place, and the rest was
either already prepared for printing in central bases or is being prepared on other
places. Automation can be lifted to the level that no one sees the page on the
monitor but making pages is being

made independently just before printing linking
the image elements from different data bases.

Newer procedures are organised in the way to image material with big memory
capacity is in the printing database beside the printing machine. The editor on its
computer manipulates only with text and image link and low resolution text. This
record, better to say organization of page layout, is connected to the informations
from printing database just before the printing so graphic editor, working only on
manipula
tions of monitor resolution, is not even aware that this bits are going into
printing. Integration of all materials is happening in the printing machine, precisely in
the computer that is the main part of that machine. The further we go to the computer
app
lication in printing, the more we find ourselves in the situation that we do not have
commercial programs which would satisfy all the possibilities of digital machines.
There has been a great quest for programmers of graphic pages specially in the field
of

individual printing application. This big title is developing slowly because three is
no recipes how to adjust to this new searching without a good programmers team.
The development of graphic programs did not overview the coming of this field of
applicat
ion that is becoming more important. We are warning to many opened
questions in typography software and reprophotography which at first were the issue
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of exploring in computer printing and still are opened for research. On this field there
has been working

together mathematics, programming engineers, hardware
specialists and art designers. Looking widely to this problems it looks like nothing is
yet programmed
-

this is how much opened issues have been left. Let us illustrate it
on monthly appearance of new

upgraded versions of programs for editing image,
text, and page layout. It is the same with the editions of upgraded program solutions
for (a few years) old digital machines in order to enhance the productivity, quality of
prints, on the same electromecha
nics.

Computing has given printing a new way of planning organizing production.
Workstation is used in the same time for all important functions; from the text editing,
diagnosing errors, fixing errors, software adjusting the register marks in multicolour
simultaneous printing, organizing waiting lines of job execution , till activating the
printing machine. Maintaining and servicing in digital printing industry is based on
diagnostic programs and devices, and is more like maintaining the computers than
mec
hanic procedures in traditional printing.

3. 8. Finishing processes in printing

Unfortunately, although in finishing processes of a printing product there has been
achieved higher automations, still computer did not take over vital actions so we
would be a
ble to say: author controls the binding, adhering, folding, moulding from
our own work desk. There is a good progress in direct managing of folding, but the
new era only begins. The development of computer application in finishing processes
of printing for
ces the digital printing. If the most usage of digital printing is on small
editions with frequent change of dimensions, material and design, and every print is
good without any rejects, than we have to make a high automation of planing a
finishing process
es, high flexibility of adjusting devices to folding, binding. Classic
method of binding allows a big waste when device adjusting on the beginning of new
geometric of finishing demands. This waste can be reduced only if adjusting the
device for finishing p
rocesses is programmed on a computer which afterwards
manipulates the devices of finishing processes.

Let us remember, typography has finished using old techniques ten years ago ,
reprophotography seven years ago, printing started to shake seriously four

years
ago. Computerizing the finishing processes is going to last the most, because here
are much larger and more versatile interests of the end
-
users, dictated by the new
perspectives of graphic designers. Subjective
-

artistic demands are tangled too
m
uch with the mechanical manipulations on final graphic product: moulding, cutting,
sewing, adhering, special colours. Demands on a final product to be preformed by
some few types of printing technique, colour and materials restrict general finishing
soluti
ons and systematic views of this problem.

3. 9. Digital printing of securities

Specific fields in printing, for example printing securities or food packages, use
several printing techniques with totally different reasons and procedures starting from
flex
o, silkprint and steel plate printing, on the same print. This graphic product use
digital printing more and more often, not as a substitute of classic printing technique
-

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but as an attempt to achieve different techniques in printing and finishing along w
ith
new program and hardware solutions.

Our best solution as digital graphics is in producing paper currency. Simultaneous
plan of multilayered print with tens of different techniques was in the beginning
simulated by computers and only after the approval
there was printing movements
were taken. By means of this a two valuably new steps were made: Unmaterial
multiple graphic finishing “till the perfection” and proofs with simulated effects and
simulated colours not fearing that the end product will be any d
ifferent from the one
approved after virtual presentation.


4. Virtual printing
-
house


Low edition and individualisation are symptomatic for the entry of digital printing
inside a complete production of printing product. We suggest changes in education o
f
graphic technologies by introducing simulators: hardware, software, animation and
training. Though experiences with simulators in printing are still on the level of a
research of this topic, we expect wide usage only when digital printing take significan
t
share in graphic production. Modelling method and simulation could become the
most efficient for accomplishing quality step forward of the production improvement,
and increasing printing skills . We are setting principles of virtual printing
-
houses as
we
ll as in schools and into departments of printing
-
houses in all sections, as well.

4. 1. Integration of conventional and digital printing


Along with the digital printing came sequential printing and individualisation
based on a variable printing plate.

Printing plate depends on the side of the computer
memory, and not on the size of a cylinder, that is a drum of the letterpress. This is the
reason for new perspectives to all activities in the process of printing, finishing, and
packaging, market and the

production organisation. When the incorporation of digital
and conventional printing features occur upon the same print
-
materials, we talk about
hybrid printing construction. Packaging is the first to open the topic of connecting
various printing techniqu
es into a unique machine, into one line with different
technologies. As an example, we give you a production of Tetra Pack in food
packaging. When a speed of the digital printing became comparable to conventional
printing, than occurs a togetherness for pr
oducing miscellaneous graphic technique
machines and herewith new usages. In front of us, there are tasks of integrated
systems. Lets mention solution to the problem: 1. Lottery demands for gamble games
requested a machine that in continuous line includes
copperplate printing, silk
printing, offset, flexo printing and an individualisation by means of digital techniques
and all this is operated by a computer. 2. complex printing of securities. Plate steel
printing is also included as well as the usage of mis
cellaneous materials and colours:
multi
-
component variable optic colours, UV colours, hologram, chinagram,
stereogram.


Package printing approaches a graphic product on the most complex way. Here
we find the need of learning the printing system by means
of modelling and
simulating on a computer. We need to design printing and finishing lines which will
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give a new product, while the current installations should be given challenging fight
by optimizing investments, especially digital printing techniques.



Computing has given the printing a new way of planning and organising the
production. Workstation is at the same time used for all important functions; from the
prepress, diagnosing errors, fixing errors, software adjusting of register marks in
multicolou
r simultaneous printing, organising the waiting lines of executing jobs, till
the printing and finishing machine activation. Maintaining and servicing in digital
printing is established on diagnostic programs and devices, and is more like
maintaining compu
ters than mechanical procedures in traditional printing.


Unfortunately, although finishing processes of printing production have achieved
high levels of automatization, a computer has not yet taken a vital operations to be
able to say: the author contro
ls binding, adhering, folding, cut out and moulding from
the desktop. Good progresses are made on the control of direct folding, binding but
the new era only begins. Printing, as a central act of the printing production, has the
most important role in the
development of computer application. Only over the
solution of connecting conventional and digital printing, along comes closing the
circle of informatization of the printing process. Computerizing the finishing processes
is going to last the most, becaus
e here are much larger and more versatile interests
of the end
-
users, dictated by the new perspectives of graphic designers. Subjective
-

artistic demands are tangled too much with the mechanical manipulations on final
graphic product: moulding cutting, se
wing, adhering, special colours. Demands on a
final product to be preformed by some few types of printing technique, colour and
materials restrict general finishing solutions and systematic views of this problem.


Specific fields in printing, for example

printing securities or food packages, use
several printing techniques with totally different reasons and procedures starting from
flexo, silkprint and steel plate printing, on the same print. This graphic product use
digital printing more and more often,
not as a substitute of classic printing technique
-

but as an attempt to achieve different techniques in printing and finishing along with
new program and hardware solutions.

4. 2. Modelling and simulating in printing


Process of graphic production has s
hown the need for a research of “tight throat”
in the production, adjusting capacities to a single task, optimizing the exploitation of
printing
-
press, and finishing machines, organizing servicing, planning the exploitation
of informatic equipment in prepr
ess and reproduction photography and configurating
a computer network. Graphic worker is not only a repro
-
photographer, printer,
typesetter, packager, but he also works in many printing phases and a specialization
is of a short period of time. All this lea
ds to the need of organizing totally new way of
the approach with multidiscipline know
-
how.


Simulation should be applied to several levels. At the beginning, let us point out
that the reason of this suggestion lays on the fact that all current graphic m
achines
are controlled by a computer. Because of this it is possible to isolate this part of a
machine directly controlled by a worker and use it for training, simulating the
production, where its impact on the process of production cease. Graphic worker
u
ses the tools that are more software than hardware. He can repeat many times the
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procedures of managing the production, without the real material expenses which
would be present in the real printing, binding and plate making.


The development of simulato
rs in printing has two direction. The first one is
making software solutions, which by means of interactive animation enables the
device configuration, imitation of work and managing the devices, changing
parameters of simulation models in the place of rea
l condition and in the place
beyond the technical limits. This software tool is installed to PCs, so training and
learning can be preformed in a classroom and at the workplace. Another direction of
the simulators development is making special devices made
of software hardware
elements of printing machines
-

which are still not handling paper and not using
colour. This devices give the feeling of physical operating of printing and finishing
processes without making material expenses. The development of elect
ronics for
simulators should be directed to enable its operating controlled by PCs. The software
of the simulation model should be totally independent from a computer and from
analogue parts of the simulator, which by the way, are necessary in many imitati
ons
for adequate problem solution in the production.


Simulation provides a research of systems which do not exist and are not
included in digital printing solutions. Simulators can be forced to the environment
which would, in the real printing, produce
big material losses. If this kind of simulators
occur; bad and good workers would suffer; simulation provides experimenting in
extreme situations. Because of security, “real system” does not allow coming near to
the marginal conditions given in machine man
uals. By managing the printing and
finishing processes of hybrid configuration in the field of marginal conditions, the
most precious experiences are made, and this is provided only by a computer
simulation. With this, systems which do not exist are studie
d, or systems which are
not allowed; but the results of this studies lead us to the fields of printing and finishing
machines development, or to new organizations for managing the graphic production.
Simulation provides a “time
-
to
-
time” knowledge test, exa
mination of worker`s skills.


Completely different chapter of simulation in printing and finishing answers the
question we would get by conducting the new technology, by building new capacities,
and joining it with current equipment. Digital printing
-
pre
sses are designed for a
shorter period of time than the conventional ones. Because of the greater electronic
and computer part in the value of the digital machine, and a strong electronic growth
on the other side, it is truth that we will change this moder
n machine division. With
this challenge we will obtain new knowledge, new organisation, new parameters of
optimizing the production. New education, new training, optimization can successfully
be carried out only on simulators and simulating software on com
puters that we have
for everyday use.


Today digital printing and a printing with plates processed by a computer (CTP)
requires high profession knowledge and assembly skills. This phase is expensive,
and if it is not done correctly
-

huge losses will occ
ur in the immediate printing. In the
environment of assembly, there has to be special printers which simulate printing
before the plate is made, all the way to the approval. That way simulation in an
assembly is useful not only in the process of learning,
but as a parallel procedure
before the real printing as well; as a basis of the security of production. Planning and
designing the assembly in many situations returns the prepress back to the
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beginning. Simulation shows negative characteristics of current
expatiations of
printing capacities. Bad characteristics of high automatization relies on the
consciousness of the worker; errors, indolence and shallowness can be fixed before
the printing of the long run. This cognition lowers the concentration and serio
usness
of the graphic worker towards the job. But waiting on fixing the prepress and repro
-
photographic errors is so high that assembly simulation is sometimes more of a waist
than of a use. The only way to get out of this is in attesting workers and every
day
training on an assembly simulator.


Here we give a suggestion to gradually introduce methods of simulation in a
graphic production. The first analogue simulators and printing should cover the area
of press: colour amount control, paper adjustment and

many more. Simulators as
software solutions should be development as a prior step to analogue simulators.
However, many printers rather believe their own ability, manufacture skills and
gained experience, than to use training machines. Only the digital ma
chine make
identical proof of the final print, so one could say that a printing press is a simulator
for training at the same time. How can we simulate printing when the only proof of
quality is a real print on the paper? We need to develop printing simula
tors which
produce only one print, but under the same conditions as a long run print. Many tried
to develop a standardization of managing colours on different printing presses.
Although many methods are suggested, final solution is not yet found; which wou
ld
guarantee that prints of the same prepress
-

but produced on different machines are
identical.

4. 3. Multimedia methods of a virtual print
-
shop


Simulation models for binding, finishing, folding and expedition would be realised
the best by a computer
animation of a modern multimedia technology. Fortunately, by
general multimedia movement, many tools were developed. First video animations
without interactive participation gave good results in schools for graphic education,
because students could have be
en introduced to a number of finishing graphic
processes. Today teaching methods require creating a virtual printing
-
house, with a
goal for enabling examination of many knowledge in a short period of time. Training
laboratories does not seek for real machi
nes, but rather a software virtual
environment with the only goal to increase the knowledge. Visual three dimensional
software graphic simulator is the only “milje” which in the same time offers motivating
situation of learning the new technologies. Multip
le repetition, managing a process
with different parameters, fixing a model without a material expense, is the best way
to learning and understanding the printing processes.


Schools have only a small number of a real system of modern printing, while
alm
ost no one have a complex hybrid printing. Visiting good equipped printing
houses, except for the huge time loss, has not given any adequate picture and
knowledge of different binding systems, folding and many other that are very
developed in the graphic i
ndustry. Learning on real systems of printing is too much
like a manufacture
-

usually for one particular machine, not viewing systematically.
On the contrary, by a simulation on a computer, many techniques are absolved in a
short time.

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Current multimed
ia programs of simulating the graphic scenario, are developed
on a modular way. A language and tools for creating interactive visual simullations of
printing processes are developed. A chance is given to explore and create own way
of operations without unp
leasant consequences, without material expenses, without
a real waste. This leads to the possibility of thinking about dynamic printing house.
First, by a computer simulation, prove the wellbeing of the suggested configuration,
and than really make it come

true.


Digital simulation of a printing process and finishing must cover continuously and
discreet modelling. Continuously situation will be applied in processes that in one
machine have different printing techniques. This models have a task to adjust th
e
speeds of passing a printed material through different parts of a machine line. If we
are dealing with devices which do not belong to a unique unit, than it is necessary to
adjust the production speeds regarding the usage of certain parts of equipment. I
n
cases like this “tight throats” happen which lead for the need of a new investment.
The results of this simulation experiments are processed by a table calculator.
Decisions on setting “the best configuration” of the production line need a
reconsideratio
n of more complex view: by including interactively new devices into
configuration of a production line and collecting a data, we return to the level of
simulation with a goal to restore a model, and after a new plan of simulation
experiments, to restore th
e real printing configuration.


Discreet simulation is necessary there where a production process includes the
most versatile techniques and technologies. This situation occurs when each
technological unit functions alone, while a complex graphic product
, for it’s
realisation, needs cooperation of several, from the point of exploitation, unadjusted
equipment. Discreet simulation of the single phase with a goal to detect optimal
exploitation leads us to stohastic modelling. Here we take parameters of the d
elay
specially for a printing machine, for materials, colour or human factors. In order to
approach the research of these “tight throats” in production using stohastic methods,
it is necessary to collect the data of a machine work during normal production

conditions. Stohastic process will give a good insight of the current situation. We will
get a firm basis for making a basic model which will serve for valuation and
verification of work of the model during different experiments.


A suggestion of modell
ing and simulating the printing, because of it’s
complexness , it will open many issues in printing, start deeper thoughts and above
all, provide a better management of a printing house. the results of this activities are
necessary because before installin
g the automatisation into graphic production,
where there are needs to integrate the press, finishing, repro and typesetting; as well
as ordering and expedition, into a unique informatic management system.


The simulation introduce us to a new perspectiv
e of printing and finishing
processes. Traditional education methods and optimizing graphic production become
too expensive and ineffective. Our idea is to install simulation models and techniques
into printing, with a declaration that it is the best way o
f adequate teaching hybrid
printing and finishing configurations in the graphic production. Simulation can be
preformed partially by a software on the simulators on
-
line or off
-
line. After a
complete obligatory education, simulation is the most efficient m
ethod for further re
-
education. Within graphic workers, there needs to be developed the knowledge to
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make them lead the scenario creation for the simulation models, because they alone
can set deep and complex questions and tasks. The simulation development

in
graphic education will continue. The best way into direct the development towards
visual, interactive, multimedia programming of simulation model in a complex
printing.

5. MIS (Management Information System) IN GRAPHIC PRODUCTION

Manipulation of the j
ob flow is the key issue in deduction of the expense, time and
the control of the printing procedures. Creation of the graphic product has some few
phases and a great number of unrelated steps. This has slow down the initiation of
standardisation in printi
ng, so many software tools were developed, which have been
treated in praxis merely as useful devices. Improvement of the efficiency can be seen
in initiation of computer management of total production flow, but the usage falters
upon many specifics not on
ly in a graphic product, but of a machine and team
environment in a printing
-
house, as well. We are at the beginning of the activities of
organizing a database containing the new suggestions and solutions of a computer
integration of the production. We are

moving towards the goal: setting the standards
in the printing production in the way to include trends of the upgrowth of the digital
printing, computing and the Internet.


5. 1. Printing and e
-
publishing

Printers in the last decade had successfully compl
eted their transformation from
the leaded cliche manufacture towards information and computer technology.


They became aware that this is the only way to survive and save activity which
upon this field has a shining history. Printers has shown their positi
ve respect
towards electronic media. IN a short period they crossed over ten software and
hardware interchange and they ask themselves when will they stop buying and
installing new and new solutions. More than ever has the need for standards been
expresse
d, and this would mean we are approaching the end of the need of the
development of new technology in needfulness the press. Printers are turned over
towards their biggest opponent: Electronic book . Printers a commitment to see and
perceive the depth of

the variation in the press and publishing which carried by the e
-
book . Only this is how they shall be able to survive. Those who shall ignore the
emergence of the e
-
book, e
-
press, e
-
magazines, shall disappear from the graphic
activity.

Professional graph
ic production today takes in net
-
system (worldwide net) as a
base of a transmission of information on a commercial platform, repro
-

typography
segment, letterpress and all the rest steps in realization of a graphic product.
Printers today are prepared
and educated in jobs of the transmission and receiving
immaterial originals; photographs, arranged text of the entire page, between the
author, lector, printer, and manipulation of the parameters in making the electronic
printing
-
plate.

We are opening the
new training to approaching a book, newspapers, magazine
publication,... Instantaneously printing products are being made as well as the
products for the Web and the Internet. A book for printing must have highly memory
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structure due to the raster reproduc
tion techniques. Opposite to this, electronic
publication of a book is adjusted to the resolution of the monitor and optimization of
present
-
day telecommunication speed situation and the cost of image transfer. A
book on the electronic media, CD or DVD for

example, is between these two
extremities. Our studied are led by a premise that this is a unique job: printers spread
them selves towards the Web and electronic design towards printing standards.

The speed of development and Internet usage is greater tha
n the development of
data transfer speed. For now, transmissions by the telephone lines speed down the
development of total immaterial graphic communication usage. Compression of the
action, though in certain circumstances dangerous, have the usage on the
transmission but not on managing the total job of page layout and printing itself.


While the image manipulation is solved by means of already well developed and
adjusted programs, a segment closer to the printing production has not got the
standards. Thes
e standards have to be formed by the manufacturers of letter
-
presses , as the conventional ones thus the digital ones as well, along with those
who contemplate and develop telecommunication systems. In order to transfer data,
that came to a printing
-
house
by the net, towards the letterpress they have to be
completed, elaborated and changed because still there are no standards which
include manufacturing the printing
-
plate and the manipulation of the electronic part of
the printing. Therefore, the developmen
t of communications system in printing
gravitates towards setting the series of protocol of integration and automation for
printing job description. Those protocol include the net transmission, manipulation of
the letter
-
presses and commercial industrial s
oftware. Intention is to make the
environment for “on
-
line” printing which joins technical aspect, functional, structural
and commercial. In a discussion on the definition and issue of the MIS “ultimate
users” are included, which in this development incor
porate thoughts of their specific
demands.

5. 2. The printing production integration

Computer integration of printing production (Computer Integrated Manufacturing) in
graphic industry tend to complete integration and automation of all design processes.
St
udying this topic has been announced by Agfa
-
Gevart, Adobe, Heidelberg and
Roland two years ago. In the last decade there were some few successful attempts
for automation production processes; for an example Heidelberg on Drupa 1995.
along with PPF (Print
Production Format) which is in a few forms a synonym for
CIP3. Other worthy example for automation of production processes is Adobes PJTF
(Portable Job Ticket Format) which is mostly used in phases of Typesetting and
Reproduction photography.


One among CI
M, there is enabling the use the newer technologies beside keeping
interests of all users, which already use programs with PPF and PJTF system. The
development is needed for program module and filters in order to minimize the
investments in new equipment.
We are not talking only about practical solution but
we are talking about the system which is required to be build and adjusted to each
situation separately. The development of software stays as individually adjusting to
production that is specific to each

production capacity of a printing
-
house and for a
particular market. We are not going towards the general solution printing production.
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Intention is to create graphic production procedure base on XML whereby it provides
total flexibility regarding future
development. XML supports Internet usage in the
most efficient way.

5. 3. Standardization of the graphic production

Last year a consortium with the name CIP4 (International Consortium for the
Integration of Processes in Prepress, Press and Postpress) was
established. CIP4
with the headquarters in Switzerland is now the most attractive group for
development and standardisation of JDF (Job Definition Format). The biggest
activities are on elaborating extensions which should be accepted by CIP4,
authorised an
d recommended as segments of future JDF versions. The council, as a
parliament of CIP4 organization, consists of representatives of different
organizations; equipment producers, printing
-
houses, designers and ultimate users of
a graphic product, in order t
o provide the width of setting and than evaluating the
usage and research tasks as well. CIP4 therefore opens new departments as
according to the theme of work, interest, levels of affecting the decision and criticising
new elements, because there is neede
d a wide cooperation of all who contemplate
standardisation and integrated printing production. JDF has in a short period of time
became an internationally recognized topic. Though we are now at the beginning of
the year 2001, still on the conceptual leve
l, names of members of the CIP4 are the
guarantee that it is necessary to solve new printing situations by all possible
knowledge. Therefore it is not unusual that companies like Heidelberg declare that
they shall use JDF in all production solutions. We st
art from the thesis that CIP4 shall
provide each manufacturer and user WITH the possibility of direct informing and
active participation in progress of the JDF.

JDF describes the entire job as a hierarchy of sequences of the process with
outspread structur
e. The possibility of planning and processing in cooperation with
partners is evolving; and in cooperation with users on temporary shared parts of jobs
on different locations and different sections. JDF relies on the complete database
containing the print
-
houses capacities, design centres, finishing sectors and
specialised productions without which, it is impossible to successfully complete a job.
Apart from the static database, in every minute there are currently available
production capacities and a time
-
plan of occupation and reservation of machine and
human resources. The duration of production is assigned by means of “industrial
software” under supervision of JDF. That way, a customer and an ultimate user will
have, over the JDF, a real plan of the begi
nning and the end, as well as the
possibility of continuous insight to the situation in the production. Each workstation
can collect statistic data about calculations and price. Currently, the usage is having
difficulties mostly on exchanges of formats of
different commercial and industrial
programs; and for mostly if software tools were made with the task to solve a
particular enclosed problem.

Printing equipment manufacturers, software manufacturers, manufacturers of
finishing machines in increasing the p
roductivity are all concentrated to decrease the
time of machine setup, and are less concentrated on the development of increasing
the working speed of those machines. CIP4 has an opinion that the entire process is
one unit and it develops the conditions o
n compatibility of all machines, and of course
those of the different technical solutions. MIS (Management Information System) and
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JDF became the key
-
issue in the communication between the customer, producer,
between a supplier and customer while controlli
ng the production process. MIS has
to became integrated in the control system of production equipment and system
managing the production flow of a graphic production. Net systems and net
communication became the reality, and they have a bigger and bigger r
ole between
all sectors of the graphic production. The MIS usage will improve the performance by
means of bigger usage of the computer plans and a production schedule. New
methods and better planning is necessary because: First; production processes with
the new machines becomes more authorised and they need to prove the investment
payout. Second; average time of printing is decreased, a space for greater number of
orders evolves. Third; continuous development of algorithms and lower price of the
computers

opens new possibilities to automatic rescheduling processes of the
printing production.

Standards will be settled when printing will no longer need more powerful
computers. This is what happened with typography ten years ago; soon enough this
will happen
to reproduction photography while there is no way standards could be
settled in digital printing at least not ten years hens.


5. 4. Managing the production and automation in printing

Installing the digital systems in printing
-
houses, we introduce new know
ledge of
graphic technology. The communication network in a printing firm is spreading to
external subjects: suppliers and publishers. Automation of the separate production
process is spreading towards complete business constructer. We suggest
approaches t
o this topic: First; the aim is to achieve bigger speeds of certain
operations and to decrease routine functions. Second; printing that includes bigger
amounts of paper and different processes is preformed automatically. Third; because
the structures in pr
inting houses stays the same
-

the way they were up till now, a
software should be adjusted to the optimal process management of informations from
database. Fourth; to develop virtual print
-
houses
-
organisations in order to study the
international processes

as one unite organisation. Improvement on of the business
can be significant with totally new business and marketing possibilities. Fifth
approach to automation in printing is based on the emergence of hybrid system.
There we have the widest space of wor
k but also the hardest, because it has to
harmonize the technology of conventional and digital printing. “New graphic
engineering” has the task to activate all powers on the contemplation of further
problem: integration of prepress, printing process and o
perations after the printing.

Central activity of our researches is directed towards the standardisation of
managing the work flow. Chapters are as follows: managing all phases of work flow,
adjusting and managing colours, computer construction of folding
, cutting, computer
fitting, organizing the database of own MIS to be used inside the company, and in
some way is a shield from the competition. Towards the outside information and data
with the characters of a company´s efficiency are available. This proc
ess is an
interactive one, for improving the production. The result is a significant improvement
of productivity by greater equipment usage, staff exploitation and further automation
development.

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We have set ourselves a task to explore the integration of t
he entire graphic
production, not only it’s particular areas. There a virtual print
-
house will become an
issue as a base of all planning. By making the problem of printing an international
one is important, because there is no unique segment which solves m
odern demands
in one hand, directed by end buyers and their demanding technologies, and on the
other hand the designers with more and more new suggestions.

The digital printing did fulfil and improve some empty holes by itself. Digital printing
is a centre

of the activity of the successful automation and is also the biggest mover
of new activities development in graphic production. By itself, digital printing includes
sophistical computer presence. This simplifies the development of managing the
printing pr
ocesses by means of methods of high automation. Important informations
offered by digital printing software shall motivate discussion of those MISA thinking
and of others, not to mention the entire graphic systems.

There is no chance integration of produc
tion and business managing systems will
emerge if we connect modern printing and a letter press printing for example, unless
we do not perform computer management in other techniques. This has to be offered
by the manufacturers of a conventional equipment

-

from the steel plate printing to
the silk printing for example. The same manufacturers offer a new equipment which
is completely in the system of incorporation to the systems of automatically managed
digital printing.

The development of printing offers
many new solutions based on conventional
technologies, digital printing and on the automation by means of computers. One
issue that is inseparable is proof
-
printing, making the unique prototype of a package,
repetition, and with the same proved data manag
ing the long run production. The
machines in the sectors of a print
-
houses are originating from different sources, are
of different age and this is how it is going to be in the future. We are trying, on many
seminars, colloquial and professional discussio
ns improve thought of integration of
the graphic process. The most discussed topics are on the integration: of the MIS,
image and text processing, proof
-
printing, press, finishing and the expedite. External
components are included from the customer, mana
ging team till the buyer. Study and
incorporation into this new phenomenon is almost a must for everyone in the printing
chain.

6. New suggestions to digital rasterising

Conventional image reproduction used only the round dot in simulation of colour
shade

and value. Our researches have moved further from this praxis, because that
method couldnt be used to solve many situations of image reproduction. It looked like
FM (stohastic Frequention Modulating) will be a complete discovery. It turne out to be
good a
t the moiré solving, but it failed on the control of the dot gain.

Dot gain area of the Raster Element (RE) is confined in a square cell. That is the
reason why shape distortions appear even after the impact with the edge of the grid
and are continued till

the highest colour value. This even appears after 78% of the
tone range at the circled dot, while with triangle
-
shaped raster element it appears
already at 50% of the tone range. The best behaviour has horizontal square shape,
while strong obstruction wit
h unrecognisable shapes are found in trigonometric
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shapes. Deformations appear as lack of controlling the rasterisation, just after
printing. Selection of RE depends on a material to be printed, on colours, penetration
of colour into the paper, frequency a
nd dot gain of RE during making a printing plate.
The dot gain of RE is the most studied area. Studies consider behaviour of the circle
and diamond shaped RE.

6. 1. Dot gain of the RE

Dot gain can be related to the length
-

latitude of RE. Relation of the

latitude of
circle, square and triangle shape is 1/1.13 1/1.30 respectively, but it counts only if
given model is without a boundary line deformation. Each further shape has its own
value of latitude enlargement toward the circle and it tells us that it

is hazard to use
unstudied shapes of RE because we do not know how will the dot gain of RE behave
in the process of making a printing plate.

Triangle and circle shape is published in PostScript literature. We bring issues on
relations (including PostScrip
t formula) for certain RE which are applied in single
colour and full colour print.

Because of boundary situations of RE deformation, we use two
-
dimensional and
3D layout. Program Mathematica has enabled layout of correct rudimentary
suggestion. Discission

on selecting the RE is delivered after animation of raster cell.
Mathematica provides examination of large number of shapes which would otherwise
be left just as idea
-
suggestions, never to be tested in practise.

6. 2. Aim and purpose of the RE study

Rater
ising with “mark” owned, individual or unique, was carried out manually, by
hand of an artist making metal engraving plate. It was continued in the era of etching
metal. Now however, in all cases computer graphics is used. Engraving skills were
abandoned i
n making the original documents and valuable papers. New shapes of
RE are created by mathematical formulas, by means of Mathematica aiming the
individualisation of reproduction in order to achieve high level of security of the
graphic print. In single colo
ur process it is already tested. When talking of
individualisation
-

it means we have a parameter system of defining RE at our
disposal: on one side it is a programmed numeric value which affects the shape
(outline) of RE, and on the other hand it is a pos
sibility of selecting parts of
mathematic formulas.

Moiré emerging in applying the new RE in colour printing is yet being examined.
The conventional approach to this research is measuring the periodical Moiré after
the print. We bring you mathematical mode
l of general moiré appearance used in
simulation of prints. Thus we jump over the process of producing a printing plate and
a print itself, in order to apply new raster shapes. This area is not examined perhaps
because of the too big instrumentation needed

in producing a real analogue plate for
measuring, and on the other hand, it has not got a significant application. Still today,
for example, post
-
stamps are (in numismatic interest) rasterised by classic AM
(amplitud modulated screening) of FM (frequency
modulated screening) raster,
having no “security elements” what so ever. Simulating a rasterisation in a colour
print gives us extended insight into moiré behaviour and a control of the RE dot gain.

V
ilko Žiljak, Graphic engineering and digital prints, Page
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The authors of this article have been using this kind of
rasterisation on all
documents and valuable papers since 1991. The most exploited is the single
-
raster in
two, and three colour print. New designs are accepted in reprinting portraits and
images on bank notes and maps.

6. 3. Stohastic rasterisation

In prac
tise, our idea of stohastic rasterisation which was suggested in the early
1999 on IFRA (Munchen), is not yet wide accepted. Up till now stohastic rasterisation
is applied just as an experiment, curiosity, new design. Parameters of the stohastic
rasterisin
g are: random selection of the screening inside given edges, random
selection of shapes (from the range of permitted shapes) for give colour shade, and
controlled programming of the impulse of generating the random variables. That
impulse may be connected

to the image contains, that is to say, with a code defined
on the most different ways, totally individualised.

Experimenting is already in first imprints of the same image contains of different
(seed) starting random access string generator, has opened a
new big unexplored
area of dot gain dependence, line screening and a shape of raster element. Stohastic
method gives the ability of monitoring the most different perimeters of the raster
matter without difficult measuring of the unexpected situations. Afte
r brief control of
the stohastically rasterised models, the imprint gives the direction of examining the
neuralgic points of those areas which need more attention. Because it is possible to
simulate many situations; repeating the experiments, changing the
parameters of
stohastic rasterising and processing the data stohastically on the same computer, we
approach those fields which we could hardly find by means of conventional
procedures of measuring and which begins only when print is done by conventional
m
ethods. And those are the methods that did not allow greater number of
experiments.


6.4. Experimental design

Dot gain of the RE is quantitatively studied by measuring and qualitatively
examined by psychological colour shade perception. For this second pro
cedure, we
included students of the final semesters, who confirmed the issues of training on
reproduction photography and computer graphic. Ways to judgement of colour shade
perceived psychologically was improved by research participants. Judgement of a
co
lour shade, which is a qualitative value, is added to the judgement of a contrast
and shape as a visual perception. Because of changing the line screening and shape
of RE, visual experience of the image is changed. The next step is solidifying the
stohasti
c parameters. It is image accomplishment with single raster shapes; followed
by fixed line screenings, but with the same seed of random access number
generator.

Between those two extreme plans; simulations of gradually released stohastic
parameters are sug
gested.


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7. Conclusion

Computers have disordered traditional, arranged and standardized printing. When I
was asked whether in current digital era of printing, standards of graphic production
can be arranged, my respond was: We can instantly set roles in t
he production,
education and market of the graphic technology if You withstand the development of
computers.

In its total outgrowth, computers have touched printing too. History shall write down
the these years: from 1980. until 2010. After the 2010. one c
ould set standards for
graphic, publishing and printing activity. Further development of computing will not
intrinsically affect development of printing.

Printing is uniting itself with publishing: e
-
printing, e
-
book e
-
publishing.
Gutenberg´s book with mo
bile types was hundred times cheaper from those written
by
-
hand. That coefficient, this “heavy mass”, we have now on the threshold from a
book printed on paper to e
-
books. This “coefficient” is important warning for a
survival. Printing industry must contr
ive and work out a lot on its own outgrowth.

Digital printing does not change the conventional printing. With it, many new
techniques, technologies, appliances, new relations in publishing and graphic
engineering education have occurred. We have tried in t
his work to reach some
topics related to new issues in printing. Intention is to warn of the seriousness of very
likely situations which have big changes in job procedures, employment, qualification,
education, cleansing, outgrowth and fall of the graphic
companies.


Last 4 years author article of the subject:

-
. Žiljak V. and Pap K., “Stohastic change of bezier curve in PostScript for the
security papers”, 5th International design conference
-
Design 1998, Dubrovnik, 1998;
UDK 7.05 (063), ISBN 953
-
6313
-
20
-
0, pp. 387
-
290;

-
. Žiljak V. and Pap K., “A new linear g
rid in the design of security”, 5th
International design conference
-
Design 1998, Dubrovnik, 1998; UDK 7.05 (063),
ISBN 953
-
6313
-
20
-
0, pp. 395
-
+3qad;

-
. Žiljak V. and Pap K., “Deformacija piksla preko inverzne transformacije” Acta
Graphica 128
-
11 (1999)1,1
-
10 (UDK:681.3.066:655.2:76) pp:1
-
10;

-
. Žiljak V. and Pap K., “Minimalizacija sličnosti CMZK modela i sspot2 separacije”
Acta Graphica 4
-
99 11 (1999)4,161
-
206 UDK/UDC:655(05)CODEN: AGGRER ISSN
0353
-
4707 pp:161
-
171.

-
. Žiljak V. and Pap K., “PostScript prog
ramiranje grafike”, pp 1
-
147. FS, Zagreb,
1999, ISBN:953
-
199
-
000

-
. Žiljak V. and Pap K., “Production management for the long run digital print with
individualization based on dynamic modular print” , IC Conference, Stockholm, 1999;

-
. Žiljak V., “The conc
ept of a hybrid printing house”, III symposium of croatian
graphic experts, Senj 1999;

-
. Žiljak V. and Pap K., “Mathematical model of stochastic curves in digital printing”,
26th International Research Conference, München, 1999;

V
ilko Žiljak, Graphic engineering and digital prints, Page
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24


-
. Žiljak V. and Pap K.,
“Optimisation of individualized in long
-
run digital print”, 26th
International Research Conference, München, 1999;

-
. Žiljak V. and Pap K., “The investigation of document and securaty digital printing
procedurs”, 26th International Research Conference, M
ünchen, 1999;

-
. Pap K., Žiljak V. Sabati Z. “Simulation of raster image processor in DTP and
digital printing system” 10th International conference, Information and intelligent
system IIS *99, FOI Vataždin 1999.

-
. Žiljak V. and Pap K., “Model simulacije

dinamičkog konfiguriranja grafičkih
sustava” 4th simpozij
-

Modekiranje u znanosti, tehnici i društvu”, CROSS, Rijeka
2000. pp 107
-
109;

-
. Žiljak V. and Pap K., “Design of high volume digital print”, International design
conference
-
Design 2000, Dubrovni
k, 2000;

-
. Žiljak V. and Pap K., “Simulation models in printing education”, International
design conference
-
Design 2000, Dubrovnik, 2000;

-
. Žiljak V. “Počitačova grafika” Konferencija v počitače v umeni a humanistick*ych
vedach, narodne osvetove centrum

v Bratislave, 2000;

-
. Žiljak V. and Pap K., “A suggestion of new definition of hakftone cells in the print
with the interpretation by means of Mathematica”, PrimMath 2001, Programski sustav
Mathematica u znanosti, tehnologiji i obrazovanju, Zagreb, 200
1.

-
. Žiljak V, Thinking about the concept and development of digital printing,
International Symposium printing on Packaging, Zagreb, 2001.

-
. Pap K., Žiljak V, Elaboration of simulators as a basis of developing the digital
printing appliance in package

production, International Symposium printing on
Packaging, Zagreb, 2001.

-
. Žiljak V, Contribution to the discussion about installing CIP3/CIP4 into systems of
finalising the graphic product, International Symposium printing on Packaging,
Zagreb, 2001.