Managing Color & Graphics in PDF Conference 2004 a PDF Workï¬‚ow

Managing Color & Graphics ina PDF Workflow

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PDF Conference 2004Presented by Julie Shaffer, PIA GATF

Managing Color &Graphics in a PDF Workflow

Presented by

Julie Shaffer

Director, PIA/GATF Center for Imaging Excellence

In this session…

• PDF vs native – what’s different in terms of

color & image file management?

• Preflighting – what to look for, tools to use

• Creating PDF for print: PostScript

–Distiller & Quark 6

• Creating PDF for print

• How to avoid color & image problems

• Hot to fix common color/image issues with

Acrobat & plug-ins

PDF workflow – what do we mean?

• Exchanging composite PDF files for print

production instead of native & supporting files

How relevant is a PDF workflow?

• Seybold PDF

Usage Survey

• 2004 survey

results show

PDF is a top

preferred file

format for

“content

receivers”

Which of the file types below do you or your workgroup prefer to receive?.

What a PDF File Contains

• The graphic components of a print-ready PDF

file consist of the following:

–Vector (path) objects – can be stroked or filled

–Text (font) objects– can also be stroked or filled

–Raster (image) objects – rectangular array of sample

values (pixels)

• These can be compressed and/or be tagged

with ICC profiles, but other familiar graphic

file types do not exist within in a PDF file!

–You won’t find an EPS file or TIFF image in a PDF,

just vector or raster objects!

More stuff that can be in a PDF file…

• Annotations

–Notes, markups, hypertext links, sounds, movies

• Actions

–Open, close doc, mouseover, view page, etc

• AcroForms

–Fields can be text or calculated via JavaScript

• Bookmarks

• Embedded files (can be anything!)

• Metadata

–Simple info (Document Properties) or XML/XMP

• Security and digital signatures


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PDF Workflow requirements

• Printer must have InRIP separation capability

–Composite PDF files have to be separated for most

printing processes

• Can also print separations from Acrobat 6

• Other non-recommended options

–Create pre-separated PDF files

–Placing PDFs as images in layout application and

printing separations from there

Top problems with PDF files

1. Image resolution too low

2. Fonts not embedded

3. Wrong color space

4. Incorrect trim or bleed information

5. Inconsistency with native file (hairlines, gradients)

6. Spot color misnamed or converted to process

7. Too much compression (quality loss)

8. Incorrect page size information

9. Transparent object issues

10. Incorrect or missing ICC profile

• Based on Seybold PDF Usage Survey 2004

Good PDFs start with good native files

• Work with color in a single color space

–CMYK (typical for print) or ICC-tagged RGB

• Reference spot colors by same name every

where they’re used

• Ensure links are unbroken

• Make sure graphics abut properly

• High resolution graphics means 2 pixel per

halftone dot (300 dpi image for 150 lpi output)

• DCS images can result in low resolution

image in final PDF

Good PDFs start with good native files

• Overprinting objects in original files may or

may not be included in PDF

• Transparency used in originals may or may

not be included in PDF

–Ultimately will have to be flattened before printing

• Fonts must be available for inclusion in PDF

and legally embeddable

• Media size specified on page setup must be

able to accommodate all elements on the

page, including bleed objects

Preflight: Finding and Fixing errors

• Tools to preflight native documents

–Markzware FlightCheck

–Gluon QC

• Tools to preflight PDF documents

–Markzware FlightCheck

–Adobe Acrobat Pro 6

–Enfocus Pitstop Pro

–Quite’s Revealing & Quite a Box of Tricks

Markzware FlightCheck

• www.markzware.com

• Venerable preflightapplication on marketsince 1995, withfrequent updates

• Checks a wide rangeof file formatsincluding many nativeapplications and PDF

• Bases check on“Ground Controls”


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Ground Controls (native files) Ground Controls (PDF files)

Gluon QC

• www.gluon.com

• An extension for

Quark & InDesign

• Checks for things

preflight software

doesn’t, like

problems with copy, misaligned page

elements and consistency of rules in a project

• Think of it as a virtual proofreader

Gluon QC

Gluon QC Gluon QC

• Plug-in for QuarkXPress


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Acrobat 6 Pro Preflight

Enfocus Pitstop Pro

• Pitstop Pro is an Adobe Acrobat plug-in that

offers PDF preflight, edit and repair tools


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Quite Revealing & Quite a Box of Tricks

Quite a Box of Tricks Quite Revealing

Quite Revealing PDF: getting there

• Paths to print-quality PDF

• PDF from PostScript

–Acrobat Distiller 6.0

–QuarkXPress 6.0

• PDF direct from applications

–Adobe InDesign & Illustrator

–MacroMedia Freehand


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Remember the problems with PDF files

1. Image resolution too low

2. Fonts not embedded

3. Wrong color space

4. Incorrect trim or bleed information

5. Inconsistency with native file (hairlines, gradients)

6. Spot color misnamed or converted to process

7. Too much compression (quality loss)

8. Incorrect page size information

9. Transparent object issues

10. Incorrect or missing ICC profile

• Based on Seybold PDF Usage Survey 2004

How do we avoid image & color issues

• Assuming your original images are

spectacular (or as good as you need them to

be), how do you make sure they’re included

as such in your PDF file?

• How do you avoid color changes

• Let’s take a look

Lost Resolution

• High resolution images in a native layout

application (Quark, InDesign) can become low

resolution images in a PDF file because the

wrong tool is used to create the PDF file, or

because of incorrect settings in the PDF

creation process

• Once an image is included in low resolution -

it cannot be repaired! Back to designer to fix!

Avoid incorrect OPI settings

• Setting OPI in PDF files when you’re not in a

true image-swapping workflow is a problem

OPI settings from

print dialog in

QuarkXPress 6…

This will give you

low resolution

images in a

resultant PDF file.

If this were the image in the layout… This is what you’ll get in the PDF


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DCS images & resolution problems

• DCS files don’t work well in compositeworkflows–typically you will get a lowresolution placeholder image only in a PDF!

• Total Integration offers a Quark Xtensioncalled SmartXT that will download the highresolution data from a placed DCS image in aQuark document during the PostScriptprinting phase

• New! DCS files from Photoshop placed intoInDesign CS will come through as highresolution composite image in PDF!

More on DCS2 files in PDF

• Impressed offers a

product, DCSMerger,

that will merge the high

resolution data into a

DCS file so that it can

be used in a composite

workflow

• This is a stand-alone application and you have

to merge the files before you place the image

into the layout application

• www.impressed.de

Bad PDF creation settings can do it too

• Most PostScript interpreters or PDF creation

tools give control over image compression

• The wrong settings can strip the resolution

out of an image file

Image Compression in Distiller

• Acrobat Distiller

offers a variety of

image compression

options

–ZIP

–JPEG

–JPEG 2000 (PDF 1.5

only)

–CCITT Group 3 or 4

–Run Length

JPEG Compression

• JPEG is a lossy compression scheme

–Data is lost when images are compressed

–If files are compressed too far, artifacting will result

• JPEG compression of medium or lower will

put a dot into a white background!

• Sampling images refer to averaging and

removing pixels from raster images

–Resulting in smaller file sizes

• Distiller options are

–Average

Downsampling

–Subsampling

–Bicubic

Downsampling

Sampling Images


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Downsampling: how much is too much?

• Need 2 pixels of image data per halftone dot

• At 150 lpi, images should have an effective

resolution of 300 dpi

• An 8”x10” 300 dpi image scaled to 50% in a

layout application results in a 600 dpi image

• That’s more resolution than is needed to

represent the image once screened, so

downsampling is intended to let the user

throw that excess resolution away

But people go too far

• Some of thecanned Distillersettings havesampling set toolow

• The “Standard”default setting willdownsample allimages to 150 dpi– (if images are above

225 dpi)

Quark Export settings

• JPEG “low” in

Quark Export

means low

compression,

higher quality

• “High” means

high compression,

lower quality

• Opposite of

Distiller JPEG

settings

Places where you can get good settings

• www.ghentpdfworkgroup.org

• www.certifiedpdf.net

• www.pdf-x.com

• Your own printer…..?

Issues with wrong color space What are specific problems?

• GDI applications “RGB” issues

–Text is RGB instead of Black

–All color images are RGB instead of CMYK

• Spot colors converted to RGB or CMYK

• RGB images converted to CMYK without

correct ICC profiles


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RGB Text to Black,RGB Images to CMYK• Users of Microsoft Office products are using

these applications for print production work

–It’s not something we recommend, but we can’t

deny that it is happening!

• PDF files created using Microsoft Office

products will commonly contain RGB black

text and RGB images even if original is CMYK

or a spot color

–Some output devices will automatically convert

RGB objects to CMYK, so that in this case, the black

text will print on all four plates

Avoid RGB Black Text–1

• Set up the AdobePDF (or Distiller)printer as thedefault printer,navigate to thePrinters and Faxessettings window

• Right-click theAdobe PDF iconand choose Set AsDefault from thepop-up menu


• Once that’s been

done, right click the

Adobe PDF printer

icon again and select

Properties from the

pop-up menu


• Under the DeviceSettings tab, set“Convert Gray Text toPostScript Gray”

–This will prevent thedreaded “RGB blacktype” problem fromOffice application files

–This is the default settingfor the Adobe PDF printer

–If you’re still using theDistiller printer, you willhave to set this manually

Avoid RGB images & illustrations

• Save graphics in

EPS format &

place these in

layout application

• Will pass through

driver without

conversion to

RGB

PDF from OS X “Save as PDF” may be RGB

• Out of the box, the

“Save as PDF” from

the print dialog under

Mac OSX will result in

RGB colors in a PDF

• You must use the

ColorSync Utility to

create filters to get

CMYK color using this

method


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ColorSync Utility

• ColorSync filters can include color conversion,

compression and PDF/X-3 compliance

Using the filter

• The filter is used when

you select it along

with using “Save as

PDF”

• Only available through

non-DTP applications

How to repair “RGB-damaged” PDF files

• Quite Software’s Quite a

Box of Tricks

• Enfocus PitStop Pro

–(check out Actions available

on their website to automate

repair process)

Use ICC-profile to convert!

• Pitstop and

QABOT will do a

better job of

converting RGB

to CMYK if you

use a good ICC

profile for the

conversion

Solid builds can be converted to spot Entire document remapped


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Problem: PDF doesn’t match original

• Many of the things we’ve already discussed

adds up to the PDF not matching original

• How the PDF is made really makes a difference

• Problem issues, like colorized TIFF images

from Quark converting to process in a PDF

can be resolved by using the tools properly

Try Quark 6 DeviceN setting

• DeviceN is a

PostScript 3

operator that

allows an object to

be defined by

more than one

color–Like a colorized TIFF

image or a spot to

process blend

–Without special help

these will result in

CMYK color in PDF

Quark 6 : Device N

• The new Device N

color option in Quark

6 eliminates the need

for special plugins to

maintain things like

spot colors in

colorized TIFFs or

spot to spot blends

Quark 6 : CMYK = CMYK & spot

• Selecting CMYK

results in PDF files

in which spot colors

in blends will default

to their process

equivalents

• Fake duotones

(colorized TIFF

images) also default

to CMYK

Acrobat display can be part of problem

• Use tools available to help properly display

PDF files and come closer to WYSIWYG

Use Overprint Preview


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Use Overprint Preview Use Overprint Preview

Don’t Use Smooth Images

• PDF file with flattened transparent objects can

show strange lines between the objects

• These don’t actually print (in most cases) but

this makes selling the PDF soft proof to

clients more difficult

• Here’s what we’re talking about, and how to

fix it…



• Open Acrobat

Preferences and

select the

Smoothing option

• Uncheck Smooth

line are and

Smooth images

Lines disappear


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Wrap up

• A PDF file can include everything you

intended from the original, as long as it was

created properly!

• PDF files with color problems can often be

corrected with tools like Pitstop or QABOT

Thanks for listening! Questions?

• The all-new PDF PrintProduction Guide

–Over 270 pages exploringthe problems, solutions,tools, and techniquesspecific to using PDF inprepress

–Covers Acrobat 6 andMac OS X

• Order now atwww.gain.net–Click on the bookstoreand products button

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