Digital Prepress

2. 7 Digital Prepress

3. 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.

4. 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.

5. Digital Basics • Digital prepress system • Computer has three main functions • Binary system is used • Bits • Bytes

6. 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

7. 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

8. Memory Types • Random-access memory (RAM) • Hard drive • Capacities are measured in megabytes or gigabytes • Almost unlimited storage capacity is available with RAID

9. 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

10. Input Devices • Keyboard • Mouse • Modem • Scanner • Voice recognition system

11. Output Devices • Monitors • Printers • Imagesetter and computer-to-plate devices • Page Description Languages (PDLs)

12. 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

13. Printers • Ink-jet printers • Project tiny droplets of ink onto paper • Make color proofs of graphics and page proofs (Epson America, Inc.)

14. Printers • Laser printers • Print enginescreate bitmapped images • Toner is fused onto paper

15. 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

16. 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

17. Preparing Content • Text preparation • Graphics preparation

18. 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

19. Graphics Preparation • Create and save graphic images • Paint programs • Draw programs • Digital photography • Electronic scanning • Graphics editing • Full-featured image editor

20. Bitmapped Images • Aliasing may be reduced by: • Antialiasing • Smoothing • Antialiasing may make images fuzzier • Autotracing converts bitmapped images into vector images

21. Vector Images • Bezier curves • Advantages of vector images: • Less image degradation • More flexible than bitmapped images • Better for high-resolution output

22. Digital Page Composition • Composition software features • Master pages and templates • Importing text • Importing graphics • Font formats and management

23. Composition Software Features

24. Composition Software Features • Pasteboard • Page grid • Drop-down menus • Context-sensitive menus • Dialog boxes • Palettes • Tool palette

25. Master Pages and Templates • Different attributes can be set up as types of master pages • Templates incorporate different master pages and other formatting

26. 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

27. Importing Graphics • Bitmapped images and vector images may be imported • Digital images can be manipulated • Drag-and-drop manipulation • Color separations, producing separation plates

28. Font Formats and Management • Font utility software • WYSIWYG representations • Easier activation of font sets • Vector fonts and PostScript vector image fonts

29. Font Formats and Management • 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

30. Font Formats and Management • 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

31. Font Formats and Management • 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

32. Font Formats and Management • Organize fonts with filing system • Easier to send associated fonts • Easier to reconstruct document if problems occur • Better way to avoid mixing fonts

33. Font Formats and Management • 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

34. Creating Digital Image andDesign Files • File formats • File names • File compression

35. 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

36. 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

37. 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

38. 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

39. File Compression • Lossless compression algorithms • Can reduce file size by about 50% • Lossless compression methods: • PKZIP • Huffman method • LZW • RLE

40. File Compression • Lossy compression algorithms • Improved speed of transfer with loss of data • Lossy compression methods: • DPCM • JPEG • Selective compression

41. 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

42. 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

43. Proofreader’s Marks

44. 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

45. 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

46. 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

47. 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

48. Digital Prepress Workflow • PDF workflow • PDF file is used to create plates or film • Allows incorporation of extended job ticket

49. 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

50. 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