• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Offset Printing Technology • • • • • • • • • • • • • • •
Prepress Basics
• • • • • • •
• • • • • • •
• • • • • • •
• • • • • • • • • • • • • • • • 2 Print Media Academy • • • • • • • • • • • • • • • • • Media consultancy – Print production Printing is communication •
Communication intention of the customer
•
Media consultancy – ideas – sketches, rough drafts
•
Ideas about the final product – layout: binding proof
•
Production planning
•
Digital prepress
Print Media Academy
Print production processes
Prepress
• • • • • • • • • • • • • • • • 3 • • • • • • • • • • • • • • • • •
Press
Postpress
Print Media Academy
Print production processes
• • • • • • • • • • • • • • • • 4 • • • • • • • • • • • • • • • • •
Digital prepress – Converting the communicative idea: Digital print pages are produced with the aid of a layout program on the computer Printing plate imaging – A processor (RIP) converts digital pages for offset printing into extremely fine dots – A laser writes these dots separately for each printing ink onto a printing plate
Print Media Academy
Print production processes
• • • • • • • • • • • • • • • • 5 • • • • • • • • • • • • • • • • •
Sheet-fed offset printing – Printing: optimum transfer of visual information onto a printing material – Data from prepress can control presettings and the ink coverage in the print – High-end production makes extremely high demands on productivity and quality in the printing process – Prerequisites: process preparation, color measuring technology and control technology
Print Media Academy
Print production processes Print finishing A finished product is produced from printed sheets – folding – gathering or collating the folded sheets – stitching, binding – cutting and ... The printed product is finished!
• • • • • • • • • • • • • • • • 6 • • • • • • • • • • • • • • • • •
Print Media Academy
General prepress workflow
• • • • • • • • • • • • • • • • 7 • • • • • • • • • • • • • • • • •
Digital sheet assembly and imposition Layout proof:
• Creation of individual pages
Proof of the whole printing form
• Proof: Positioning and color • Color and text corrections
Output: Computer to Workstation • Layout • External data transfer • Record, create, process data: text, images, graphics • Design pages
Server (data management)
film / plate Generating CIP4 data Data exchange • Printing press • Postpress
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 8 • • • • • • • • • • • • • • • • •
A print page may contain various elements:
Text
Image
Graphics
Scanner, Digital camera
Computer, software
ABC ewç59 Computer, software, fonts
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 9 • • • • • • • • • • • • • • • • •
Artwork masters: Lineart masters – Only binary tone values can be printed in offset, i. e.: print or not print! – Lineart masters consist only of such binary elements: smooth “solid” line or no line – Single-color or multi-color lineart masters can be processed
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 10 • • • • • • • • • • • • • • • • •
Artwork masters: Continuous-tone images – Images with a smooth progression in tone values: • monochrome = tone values only in gray scales • color = tone and color values – Continuous-tone images must be converted technically, to obtain binary printing elements, i. e. continuous-tone images must be screened
Print Media Academy
Master copies for production Artwork masters: Continuoustone images • Screening - to break down an image into individual binary printing elements • Color separation - Color separation of a colored original produces partial images for printing with the process colors C, M, Y and additionally K
• • • • • • • • • • • • • • • • 11 • • • • • • • • • • • • • • • • •
Monochrome and color continuous-tone images
Print Media Academy
Master copies for production Color separation
• • • • • • • • • • • • • • • • 12 • • • • • • • • • • • • • • • • •
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 13 • • • • • • • • • • • • • • • • •
Data transfer – It is becoming increasingly common for customers to transfer digital data for the production of a printed product – External data are rarely “print-ready”, i. e. can be used for production without further processing – Deficiencies may cause • problems in keeping to deadlines • interruptions in the production process • higher costs Data exchange: flyer title
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 14 • • • • • • • • • • • • • • • • •
Data transfer –
In order to avoid problems and therefore costs, intensive communication between customer and production is essential: “So that we understand each other better!” • Check list for creating data
–
In production • Systematic control of data input = preflight check in the printshop • Data management for data optimization
„Digital reminder“ for data exchange (excerpt)
Print Media Academy
Master copies for production
• • • • • • • • • • • • • • • • 15 • • • • • • • • • • • • • • • • •
The image as information medium !
Digital processes allow images to be produced synthetically
!
It is rare to be able to recognize: true or false?
!
Often the computer is used to create a "new" image from various other images and additional editing
!
Composing = Manipulation?
!
We are influenced more by an image than any text
Print Media Academy
Master copies for production ... and this is how a new facade is produced !
lying with pixels?
!
digital tools "make“ images
• • • • • • • • • • • • • • • • 16 • • • • • • • • • • • • • • • • •
Print Media Academy
Light and color Our colorful world Color is an everyday sensory experience that we take for granted -
Color ... •
provides information
•
is decorative
•
affects us
•
signalizes
•
classifies
•
shouts and ...
• • • • • • • • • • • • • • • • 17 • • • • • • • • • • • • • • • • •
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 18 • • • • • • • • • • • • • • • • •
Our colorful world – Color is an optical effect, i. e. a sensation conveyed by the eye and brain – Nature itself is colorless. It only gets its color through light – Color is light
Color in the system: CIELAB color solid
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 19 • • • • • • • • • • • • • • • • •
How do we see colors? –
White light strikes an object
–
Light rays are absorbed and reflected at the surface
–
Reflected light rays reach the eye
–
Color receptors in the human eye react to the received rays and pass them on to the brain • cone-shaped receptors react to “colored” rays • rod-shaped receptors react to black, white, gray
• • • • • • • • • • • • • • • • 20 • • • • • • • • • • • • • • • • •
Print Media Academy
Light and color White light
Color receptors in the eye Colors of the spectrum
Light source Prism • Model: A prism splits white light into the colors of the spectrum • The visual perception of the beams takes place in the eye, the brain adds up all of the spectral energy to create a sensation: An image is formed from the information received – gray or colored! • White: The total of all colors of light is received • Black: No light = no color visible
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 21 • • • • • • • • • • • • • • • • •
Additive mixing •
Mixing colors of light
•
Primary colors: red, green and blue
•
Mixing these primary colors at full intensity produces white light. Increasing the addition of the colors of light
B
R
leads to increasingly lighter mixed colors, if the intensity of the radiation is reduced, the lightness and color strength go down Examples of technical equipment that "creates" colors by additive mixing are televisions, monitors, projectors, video devices
G
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 22 • • • • • • • • • • • • • • • • •
Subtractive mixing !
Certain color components of the light rays from white light striking a body are absorbed by the body, while others are reflected = Components of the light are subtracted
!
Mixing body colors: Primary colors: cyan, magenta and yellow
!
The optimum mixture of these primary colors produces black. Reducing the components equally produces gray values from dark to light
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 23 • • • • • • • • • • • • • • • • •
Subtractive mixing in the printing process !
White paper reflects all of the light striking it
!
The more ink is printed on the paper, the more light of certain radiation is absorbed
!
The body's own “color” absorbs complementary radiation and reflects its own radiation, that is passed on by the eye to the brain: Color is a sensation
White light
Print Media Academy
Light and color
• • • • • • • • • • • • • • • • 24 • • • • • • • • • • • • • • • • •
Subtractive mixing in the printing process –
Image reproduction in four-color printing is achieved using the process colors cyan, yellow, magenta and black
–
Tone and color values of multi-color images must be separated in the correct proportion into cyan, yellow, magenta and black components
–
Screening: Each color separation must be converted into binary, printable elements
–
Autotypical color mixing: To the observer there is both an additive as well as a subtractive response
Print Media Academy
Scanning
• • • • • • • • • • • • • • • • 25 • • • • • • • • • • • • • • • • •
Digitization of images: Scanning –
Scanners perform a computer-controlled digitization of single-color and multi-color images
–
Three color separations are created by incremental scanning the original and concurrent color separation using RGB filters
–
Software converts these RGB data into cyan, magenta and yellow, taking corrections into account
–
The black color separation is produced either by using a special filter or by computation
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 26 • • • • • • • • • • • • • • • • •
Screening of images - Different tone values in the image are converted into extremely small binary print elements - Tone values can be represented by variablearea halftone dots: • white paper completely reflects incident light rays, • halftone dots of different sizes absorb more or less light! - The brain does not recognize individual dots through the eye, but rather a reflected brightness value
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 27 • • • • • • • • • • • • • • • • •
Screen ruling –
For an autotypical (variable area) screen, the distance between the halftone dots from midpoint to midpoint is always the same
–
The screen ruling gives the number of halftone dots in lines from midpoint to midpoint per unit length, e. g.
–
• l/cm
= lines per cm
• lpi
= lines per inch
The more halftone dots per unit, the finer the screen 1 cm
Screen ruling = number of lines per cm
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 28 • • • • • • • • • • • • • • • • •
Screen ruling –
The screen ruling (called screen frequency) specifies the fineness of the screen in the rendering of the picture information.
–
The choice of screen ruling depends on the printing process and the surface of the printing material
–
Rough paper surface = smaller screen ruling (< 54 l/cm)
–
High quality and smoother paper surface = higher screen ruling (> 60 l/cm)
40 l/cm screen K
80 l/cm screen K
0.100 mm Halftone value = 50% Halftone value = 50%
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 29 • • • • • • • • • • • • • • • • •
Screen angle –
Every autotypical, symmetrical screen has a regular structure, e. g. horizontal and vertical screen lines
–
In four-color printing with autotypical screening, the individual colors must be angled, in order to avoid Moiré
–
Moiré = formation of interference pattern
–
Least noticeable angle = 450, standard practice for monochromatic halftone prints and for the key color in the image
–
Standardized angle positions: 00, 150, 450 and 750, where Y is always at 00 Examples of Moiré effects
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 30 • • • • • • • • • • • • • • • • •
Screen output technology – Laser systems in imagesetters output digital print pages to film or directly to a printing plate via a raster image processor (RIP) – The smallest representable element of the imagesetting system, an imagesetter pixel, is called a dot – The size of a dot is dependent on the resolution (fineness of reproduction) of the output system
Halftone value approx. 82%
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 31 • • • • • • • • • • • • • • • • •
Screen output technology –
The resolution of an output system is given in dots per inch (dpi)
–
For a screen ruling of 60 l/cm, a screen cell has an edge length of
Rel
Dot
1 cm : 60 = 0.01666 cm = 0.166 mm –
If an output system has a resolution of 2500 dpi, a screen ruling in the print of 60 l/cm (152 dpi) gives: • Number of possible tone value levels = (2500 dpi : 152 dpi)2 = 256 • !256 = 16 x 16 imagesetter pixels
Rel = Recorder element Dot = Imagesetter pixel The laser beam requires for an area of 1 cm2 60 x 60 x 256 = 921,600 switching operations
• • • • • • • • • • • • • • • • 32 • • • • • • • • • • • • • • • • •
Print Media Academy
Screen technology Classical dot shapes and dot contact The four basic dot shapes.
2. Dot contact Cushionshaped
Square
Round
Barrelshaped
a) Square dot contact
60 line screen (60 l/cm) K
K
K=0.166 mm 0.100 mm Halftone value = 40% d+0.010 mm -> 47%
1. Dot contact
d
b) Chains Dot contact (schematic)
Halftone value = 40% d+0.010 mm -> 47.95%
Source: Ibm Training
Print Media Academy
Screen technology AM (amplitude modulated screen)
• • • • • • • • • • • • • • • • 33 • • • • • • • • • • • • • • • • •
FM (frequency modulated) screen
Source: Ibm Training
• • • • • • • • • • • • • • • • 34 • • • • • • • • • • • • • • • • •
Print Media Academy
Screen technology In autotypical screening the halftone dots for the colors are arranged at specified angles. They form visible rosettes. Frequency-modulated screening uses neither set angles nor patterns of the same shape to distribute colors.
Source: Ibm Training
• • • • • • • • • • • • • • • • 35 • • • • • • • • • • • • • • • • •
Print Media Academy
Screen technology What is FM or stochastic screening? • Halftone dots are arranged randomly (frequency modulated) • Dots are all the same size • Their position varies
Dot size is measured in microns (µ meter or 1/1000mm) A 28µ FM screen corresponds in gray values and definition to a conventional screen of about 300 lpi = 120 line screen
Source: Ibm Training
Print Media Academy
Screen technology
• • • • • • • • • • • • • • • • 36 • • • • • • • • • • • • • • • • •
• Large number of finely distributed small halftone dots • Distance or number of dots varies • Dot size remains constant • Advantages • Avoids Moiré and offset rosettes • Increase in detail resolution Much better reproduction of small type sizes particularly for script types.
• Disadvantages • Tighter specifications due to smaller dot size • Greater dot gain
Source: Ibm Training
• • • • • • • • • • • • • • • • 37 • • • • • • • • • • • • • • • • •
Print Media Academy
Creating documents Creating digital documents – Entering texts, graphics, pictures
– Integration of all elements of a print page according to the page layout
Type
– Digital proofing • Position proof • Color proof – Go-ahead by the customer
Type
Type
• • • • • • • • • • • • • • • • 38 Print Media Academy • • • • • • • • • • • • • • • • • Transfer of information to the printing form Digital code – Computers use a binary code, information is represented in the form of 0 and 1 = 1 bit (binary number) – A group of 8 bits is one byte and so 256 definitions or switching states: 1 bit = 2 definitions: 0 or 1 2 bits = 4 definitions 8 bits = 256 definitions = 1 byte
ASCII code
A A B B 1 2
Morse signals
01000001 • 01100001 01000010 - • • • 01100010 00110001 • - - - 00110010 • • - - -
• • • • • • • • • • • • • • • • 39 Print Media Academy • • • • • • • • • • • • • • • • • Transfer of information to the printing form A bitmap -
A digital, checkerboard structure of all the information
-
Recording, saving image data in scanners and digital cameras
-
-
• Control of imaging systems and printers for output The digital representation for the output consists of bit or byte data = individually controllable pixels or picture elements The degree of fineness or resolution is given as “dots per inch (dpi)”
0 0 0 0 0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0 1 1 1 1
0 0 0 0 0 0 0 1 1 1 1 1 1 1
0 0 0 0 0 1 1 1 1 1 1 1 0 0
0 0 1 1 1 1 1 1 1 1 1 0 0 0
1 1 1 1 1 1 0 0 0 1 1 0 0 0
1 1 1 1 0 0 0 0 0 1 1 0 0 0
1 1 1 1 1 1 0 0 0 1 1 0 0 0
0 0 1 1 1 1 1 1 1 1 1 0 0 0
0 0 0 0 0 1 1 1 1 1 1 1 0 0
0 0 0 0 0 0 0 1 1 1 1 1 1 1
0 0 0 0 0 0 0 0 0 0 1 1 1 1
0 0 0 0 0 0 0 0 0 0 0 0 0 1
• • • • • • • • • • • • • • • • 40 Print Media Academy • • • • • • • • • • • • • • • • • Transfer of information to the printing form Vector format –
Lineart masters and type, in which all of the elements are defined by precisely mathematically defined geometric points, e. g. vertices of a character
–
These individual vector data are connected for outputting. Only then do they produce the “filled in” character as a bitmap
–
Advantage of vector data • Exact representation is independent of size and resolution • Smaller data volumes
Print Media Academy
Imposition
• • • • • • • • • • • • • • • • 41 • • • • • • • • • • • • • • • • •
Preparation for the output of digital pages –
When printing several pages: Imposition on one printing form
–
Imposition: The arrangement of the pages on a print sheet, so that after printing, folding and processing, the pages are in consecutive sequence.
–
Imposition takes account of the: •
number and format of the pages
• •
size of the print sheet production in the printing press as well as folding and binding
• • • • • • • • • • • • • • • • 42 • • • • • • • • • • • • • • • • •
Print Media Academy
Imposition Preparation for the output of digital pages:
Trim
Trim
Trim Head
2 Printing lay
Gutter
Gutter
Head
–
7
The arrangement of the pages is determined with the aid of a folding layout After printing and folding: trim on three sides!
6
–
Trim
Example of the“inner printing form” of a 16 page print sheet
11 10
–
Trim
15 14 Foot
3
Print Media Academy
Output technologies Output of digital pages –
Computer to film • Product = film for copying processes
–
Computer to plate • Product = printing plates, imaged externally in an imagesetter
–
Computer to press • Product = printing plates, film imaged internally in the printing press
• • • • • • • • • • • • • • • • 43 • • • • • • • • • • • • • • • • •
Print Media Academy
Output technologies
• • • • • • • • • • • • • • • • 44 • • • • • • • • • • • • • • • • •
Output of digital pages –
RasterImageProcessor (RIP): conversion of the digital data into a bitmap of binary elements, the imagesetter pixels (dots)
–
Imaging: Transfer of this binary information, e. g. by laser, onto film or printing plate
–
Basis: Page description language PostScript and a corresponding software, e. g. software RIP Prinect MetaDimension
Text
Text Digital document
Print Media Academy
Output technologies Output of digital pages –
Possible functions of the RIP • Conversion of all text, picture and graphics data into a bitmap • Assignment of screens to images • Color separations of color images • Trapping • OPI: Substituting low-resolution image data in high-resolution original image data (Note: In laser and inkjet printers the RIP is already installed)
• • • • • • • • • • • • • • • • 45 • • • • • • • • • • • • • • • • •
Print Media Academy
Data formats What do the following stand for in the process? •
PostScript,
•
PDF,
•
PPF,
•
JDF,
•
CIP ...?
• • • • • • • • • • • • • • • • 46 • • • • • • • • • • • • • • • • •
Print Media Academy
Data formats: PostScript
• • • • • • • • • • • • • • • • 47 • • • • • • • • • • • • • • • • •
PostScript... !
is a page description language by Adobe, which describes exactly all elements of a page (text, image, graphics) and their position in the layout of the print page
!
is a programming language for describing print pages
!
is a printer-independent language for controlling output systems
!
Fonts or PostScript fonts, so-called Type 1 fonts, give an exact mathematical description of the outer contours of characters
Print Media Academy
Data formats: PostScript
• • • • • • • • • • • • • • • • 48 • • • • • • • • • • • • • • • • •
PostScript functions –
Application-specific changes e. g. distortion, image magnification, gradient adaptation
–
Graphical elements (pictures, graphics) are converted into halftones: dot shape, screen ruling, screen angle. Here specific settings, e. g. calibration, print characteristic curves etc. are taken into account
–
A separate bitmap is generated for each color
%!PS line width /zoll {72 mul} def /rechteck % Routine {newpath .6 .4 moveto -.6 .4 lineto -.6 -.4 lineto .6 -.4 lineto closepath } def gsave 5 zoll 3 zoll translate 1 16 div setlinewidth 116 % Schleife 1 bis 6 {gsave .5 mul zoll dup scale % multiplizieren rechteck stroke grestore } for % SchleifenEnde grestore showpage
Print Media Academy
Data formats: PDF
• • • • • • • • • • • • • • • • 49 • • • • • • • • • • • • • • • • •
Portable Document Format, PDF... is a page-oriented PostScript data format by Adobe, with which platform-independent data may be exchanged
–
produces relatively small files by reducing superfluous commands and structures
–
can be read on different computer platforms using the free Adobe Acrobat Reader
Prepress
Workflow
–
PDF file
Document PDF view
Print Media Academy
Data formats: CIP3 data Electronic sheet assembly
• • • • • • • • • • • • • • • • 50 • • • • • • • • • • • • • • • • •
RIP Production data for film/ platesetters Thumbnails Ink presetting PPF
Register marks Print control bars Color reference values Cutting marks Folding marks Stitching marks
Print Media Academy
Data formats: JDF data
• • • • • • • • • • • • • • • • 51 • • • • • • • • • • • • • • • • •
JDF- Job Definition Format ! JDF is a manufacturer-independent interface language ! Enables communication between devices in the graphics industry ! Is supplemented by status information ! Connection to MIS systems (vertical market software) ! Specification by the CIP4 consortium ! Description by so-called "ICS“ – Interoperability Conformance Specifications ! Based on the XML file structure
Management
Prepress
Press
Postpress
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 52 • • • • • • • • • • • • • • • • •
Color management system –
Prerequisite so that all components in a workflow are optimally aligned in accordance with the specified color standards
Digital proof – –
Production-based simulation of the intended printing process
Applications
Profiling
Calibration
Preview of the print result and binding basis for the go-ahead Standardization
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 53 • • • • • • • • • • • • • • • • •
Color rendering problems in individual process steps
Scanner
Proofer
Monitor
Press
Print Media Academy
Color management ICC profiles –
Problem: Graphical representation of the color space of a device • Color spaces have different shapes and dimensions, i. e. each device has its own defined color space
–
Basis of color management: • ICC profiles describe the color reproduction of an input or output device according to ICC guidelines
• • • • • • • • • • • • • • • • 54 • • • • • • • • • • • • • • • • •
• • • • • • • • • • • • • • • • 55 • • • • • • • • • • • • • • • • •
Print Media Academy
Color management Process
Standardization
Process control
Optimization Prepress
Optimization Printing process
ICC profiles
Proof and standardized print
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 56 • • • • • • • • • • • • • • • • •
Basis: device-independent CIELAB color space
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 57 • • • • • • • • • • • • • • • • •
International standards Commission Internationale d’Éclairage (CIE) – Specification of the Lab color space 1976 – Device-independent
+b +b
-a -a
+a +a
– Based on human color perception International Color Consortium (ICC) – Specification of ICC profiles 1994 – Computer-independent – Manufacturer-independent
-b -b
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 58 • • • • • • • • • • • • • • • • •
Information transfer using ICC profiles ...
Scanner, D-Cam ICC calculation for monitor, print, proof
Print Media Academy
Color management
• • • • • • • • • • • • • • • • 59 • • • • • • • • • • • • • • • • •
Profiles for input and output devices
Scanner
Proofer
Monitors
Printing presses
Print Media Academy
RIP Raster Image Processor
PDF pages: content
• • • • • • • • • • • • • • • • 60 • • • • • • • • • • • • • • • • •
Raster Image Processor
CTP or film imagesetter Printing plates Bitmaps Control data
Positioning data: control data (ink
Co zon ntrol es, data reg iste r,… )
Print Media Academy
RIP Raster Image Processor
• • • • • • • • • • • • • • • • 61 • • • • • • • • • • • • • • • • •
Calculation of the data takes place in the RIP (Raster Image Processor)
Exposure of the finished print sheets onto plates
The RIP requires data: • Content • PDF or PostScript individual pages • Control data • Positioning data for the pages and control elements
The recorder requires data: • Content • Bitmaps • Control data • Register punching • Plate selection (Multi Cassette Loader)
• • • • • • • • • • • • • • • • 62 Print Media Academy • • • • • • • • • • • • • • • • • Computer to plate/ Computer to film Technical equipment
Print Media Academy
Imagesetter systems
• • • • • • • • • • • • • • • • 63 • • • • • • • • • • • • • • • • •
Design features
– Capstan imagesetter (flat-bed) Flat-bed systems image via a polygon mirror on roll material, which is transported in synchronization with the rotation – Internal drum imagesetters Image on material that is cut to size (sheets cut to size from the roll) – External drum imagesetter Direct the laser beam line by line onto a rotating drum, on which the material to be exposed is fixed
Print Media Academy
Capstan imagesetter
• • • • • • • • • • • • • • • • 64 • • • • • • • • • • • • • • • • •
Capstan system ! !
Synchronization of the optical system Polygon Adjusting the luminous intensity mirror between the center and the edges of the material due to different beam lengths
!
Suitable for film and polyester plates
!
Low production costs
Material
Laser source
Print Media Academy
CTP imagesetter
• • • • • • • • • • • • • • • • 65 • • • • • • • • • • • • • • • • •
Internal drum imagesetter Fixed laser unit
digital data
Prism exposes image line by image line
rotating mirror optic
Mirror
Plate
Print Media Academy
CTF imagesetter
• • • • • • • • • • • • • • • • 66 • • • • • • • • • • • • • • • • •
Internal drum system !
High production costs with internal drum, film cut to size, high repeat accuracy
!
Identical beam length in all positions
!
Simple optical system (prism)
!
Only one laser beam for exposing, from roll to sheet, from roll to roll
!
Connection to the online processor
!
Integrated register punching system for films and polyester plates
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Print Media Academy
CTP imagesetter External drum imagesetter
Exposure unit is guided along the drum
digital data
optic drum
plate
Print Media Academy
CTP imagesetter External drum imagesetter •
Short beam path means higher power output
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Exposure is performed using more than one beam at the same time
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Up to 384 laser lines per revolution at the same time
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Short exposure times
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Variable optical system
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Thermal printing plates
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Print Media Academy
Printing plates Advantages and notes !
Very short production times
!
High-quality printing plates
!
Optimum register accuracy
!
Shorter makeready times
!
Less waste during makeready
!
All elements must be in digital form
!
A digital proofing system is compulsory
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Print Media Academy
Integrated production Production control and monitoring Invoicing Delivery Historical costing
Stitching
Feedback of data
Folding
Production monitoring
Cutting
Production planning
ImageControl
Process planning Material administration Job input Quotation Cost estimation Inquiry
JDF
Speedmaster CP2000
PrepressInterface
CtP exposure RIP Proofing Imposition Proofing Color management Trapping Color conversion Preflight PDF production
JDF Job Definition Format •
The JDF is a manufacturer-independent interface language
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Enables communication between devices in the graphics industry
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Is supplemented by status information
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Connection to MIS systems (vertical market software)
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Specification by the CIP4 consortium
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Described by so-called "ICS“ – Interoperability Conformance Specifications
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Based on the XML file structure
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Prepress Basics
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