7 Digital Prepress Permission granted to reproduce for educational use only. © Goodheart-Willcox...

7Digital Prepress

© Goodheart-Willcox Co., Inc. Permission granted to reproduce for educational use only.

Learning Objectives

• Identify different computer platforms.• Explain the characteristics of different

types of storage devices.• Differentiate between various output

devices.• Explain the processes used in text and

graphics preparation.• Summarize the features of page

composition programs.


Learning Objectives

• Identify the techniques used in creating digital design files.

• Explain the proofreading process.• Explain the preflighting process.• Compare types of production proofs.• Explain digital prepress workflow.


Digital Basics

• Digital prepress system

• Computer has three main functions

• Binary system is used– Bits– Bytes


Computer Platforms

• Different platforms for different computer systems

• Hardware operates various programs• Different types of software are used in

digital prepress process• Cross-platform file formats may make

process more efficient


Computer Platforms

• Macintosh®

– Designed around graphical user interface (GUI) concept

• Personal computers (PCs)– Originally command-based operating system

• UNIX®

– Open-source system upon which other platforms may be based


Memory Types

• Random-access memory (RAM)• Hard drive

– Capacities are measured in megabytes or gigabytes

– Almost unlimited storage capacity is available with RAID


Memory Types

• CD and DVD drives– “Read-only” and rewritable discs– CD capacity from 670 MB to more than

800 MB– DVD capacity from 4.7 GB to 8.75 GB

• Flash memory cards– Fast access and retrieval speeds– High storage capacity


Input Devices

• Keyboard• Mouse• Modem• Scanner• Voice recognition system


Output Devices

• Monitors• Printers• Imagesetter and computer-to-plate

devices• Page Description Languages (PDLs)


Monitors

• WYSIWYG display• Resolution and dot pitch• Monitors use additive color formation• Images print in subtractive color

formation• Color management systems (CMS)

provides WYSIWYP display


Printers

• Ink-jet printers– Project tiny droplets

of ink onto paper– Make color proofs of

graphics and page proofs

(Epson America, Inc.)


Printers

• Laser printers– Print engines create

bitmapped images– Toner is fused onto

paper


Imagesetter and Computer-to-Plate Devices

• Used for high-resolution images output for commercial printing

• Raster image processor (RIP) converts page elements to bitmapped images

• High-resolution text and graphics may be output onto paper, plates, or to a digital printing press


Page Description Languages

• Identify all elements to be put on pages

• May be interpreted by different types of software programs

• Interpreters– Receive PDL descriptions– Translate them into patterns of dots or

pixels


Preparing Content

• Text preparation• Graphics

preparation


Text Preparation

• Text must be electronic• Word processing program is used for

editing• Proofing tools increase typesetting

efficiency• Text may be coded for special

formatting in page composition programs


Graphics Preparation

• Create and save graphic images– Paint programs– Draw programs– Digital photography– Electronic scanning

• Graphics editing– Full-featured image editor


Bitmapped Images

• Aliasing may be reduced by:– Antialiasing– Smoothing

• Antialiasing may make images fuzzier

• Autotracing converts bitmapped images into vector images


Vector Images

• Bezier curves• Advantages of

vector images:– Less image

degradation– More flexible than

bitmapped images– Better for high-

resolution output


Digital Page Composition

• Composition software features• Master pages and templates• Importing text• Importing graphics• Font formats and management


Composition Software Features


Composition Software Features

• Pasteboard• Page grid• Drop-down menus• Context-sensitive menus• Dialog boxes• Palettes

– Tool palette


Master Pages and Templates

• Different attributes can be set up as types of master pages

• Templates incorporate different master pages and other formatting


Importing Text

• Text usually comes from a word processing program

• Text filters may be used for formatting• Style sheets

– Paragraph style sheets– Character style sheets


Importing Graphics

• Bitmapped images and vector images may be imported

• Digital images can be manipulated– Drag-and-drop manipulation– Color separations, producing separation

plates


Font Formats and Management

• Font utility software– WYSIWYG representations– Easier activation of font sets– Vector fonts and PostScript vector image

fonts



• PostScript Type 1 fonts– Characters are stored as language

programs– Two component files

• Suitcase file• PostScript printer typeface file

– Font packages may include various weights and widths



• TrueType fonts– No specific sizes– Combine screen fonts and printer

typeface into one file– May need to use a substitute PostScript

font if used with a PostScript output device



• Multiple master fonts– Allow variations to be created from a

base design– Use base fonts that have one or more

instances of that font– Include one or more design axes for more

variations



• Organize fonts with filing system– Easier to send

associated fonts – Easier to reconstruct

document if problems occur

– Better way to avoid mixing fonts



• Font report– Way of verifying document fonts– Page composition software may compile

document reports

• Preflighting fonts– Helps avoid problems when documents

are sent to printers– Alerts when fonts are missing


Creating Digital Image andDesign Files

• File formats• File names• File compression


File Formats

• Tagged image file format (TIFF)– Raster graphic file

• Tagged image file format for image technology (TIFF/IT-P1)– Device-dependent format

• Encapsulated PostScript– Can be used in open press interface (OPI)

systems


File Formats

• Windows® Metafile (WMF) and PICT– Graphics files for different platforms

• Desktop color separations (DCS 1.0 and DCS 2.0)– File that has six plates and a master

image

• Graphics interchange format (GIF)– Supports raster images up to 256 colors


File Formats

• Portable document format (PDF)– Standard for electronic document

distribution– Universal file format that preserves all

aspects of native files– Simple, compact vector files– Page-independent


File Names

• Helps keep work organized• Must be consistent• May be subject to conventions of

computer platforms or programs• Revised files should use different

names


File Compression

• Lossless compression algorithms– Can reduce file size by about 50%

• Lossless compression methods:– PKZIP – Huffman method– LZW– RLE


File Compression

• Lossy compression algorithms– Improved speed of transfer with loss of

data

• Lossy compression methods:– DPCM– JPEG

• Selective compression


JPEG File Format

• Popular standard for images used on Internet– Extreme compression capacity– Ability to support 24-bit color

• Major goal is to maintain appearance of image rather than data contained in original

• Functions best for color and grayscale, continuous-tone images


Proofreading

• Proofs are typically printouts from laser printer

• Proofreader’s responsibilities– Check spelling and hyphenations– Verify consistent style– Check for omitted or repeated copy– Use proofreader’s marks to mark up copy


Proofreader’s Marks


Proofreading Methods

• Comparison proofing– Checks for obvious errors or changes– Proofed next to manuscript– Must compare proof with copy

• Two-person proofing– Reader and copyholder– Proofreaders read to each other


Spell Check Programs

• Incorporated into word processing programs

• Compares words in documents with those in program’s dictionary

• Copy must still be reviewed by proofreaders


Preflighting

• Orderly review of files to identify items that could cause problems at output or prepress stages

• Common problems– Fonts and trapping missing or incorrect– Incorrect color or file format– Graphics missing or not linked– No laser proofs supplied


Production Proofs

• Soft proofs– May be delivered via e-mail or accessed

on Internet– Review takes significantly shorter time

• Digital proofs– Laser proofs and ink-jet proofs– Ink-jet proofs are inexpensive but do not

show moiré patterns


Digital Prepress Workflow

• PDF workflow– PDF file is used to create plates or film– Allows incorporation of extended job

ticket


Digital Prepress Workflow

• Job Definition Format (JDF)– Based on XML– Similar to embedded electronic job

tickets– Information and instructions in JDF files

may be manually changed


Soft Proofs• Becoming more widely used than digital

proofs• Reduce use of paper in multiple rounds of

checking proofs• No transportation is involved in transmitting

because they are sent over Internet• Quality of soft proofs can be questionable


ReviewWhat are three major types of computer platforms?

Macintosh®, personal computers (PCs), and UNIX®


ReviewWhat are flash memory cards?

Flash memory cards are small, removable storage devices that have high storage capacity with fast access and retrieval speeds.


ReviewHow do ink-jet printers function?

Ink-jet printers use print heads that project tiny droplets of ink onto the paper surface.


Review

What two processes help reduce jagged lines in bitmapped images?

Antialiasing and smoothing


Review

What is the major work area called in page composition programs?

Pasteboard


Review

What palette is the most often used because it allows the operator to perform many different layout functions?

Tool palette


Review

What is the standard format for electronic document distribution?

Portable document format (PDF)


Review

What type of algorithm refers to a data compression process in which some data is lost?

Lossy compression algorithm


Review

What are the two different proofreading methods?

Comparison proofing and two-person proofing


ReviewWhat is preflighting?

Preflighting is an orderly review of files to identify items that could cause problems at the output or prepress stage.


Review

What are the two most common types of digital proofs used today?

Laser proofs and ink-jet proofs


Review

What is an extended job ticket in PDF workflow?

An extended job ticket is an electronic document that contains all the instructions required for processing a job.

7 Digital Prepress Permission granted to reproduce for educational use only. © Goodheart-Willcox...

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Transcript of 7 Digital Prepress Permission granted to reproduce for educational use only. © Goodheart-Willcox...