1. Digital Art Preflight and Analysis
Society for Scholarly Publishing
Baltimore, MD
27 May 2009
Chris Coleman, Digital Specialist,
Greg Suprock, VP/GM
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2. Digital Art Preflight
What is Preflight?
– An objective review of an image designed to identify:
– Resolution problems,
– File format issues,
– Color space concerns that may compromise quality,
– Other problematic issues that could affect reproduction.
What Preflight is not…
– A way to evaluate the context of the image…that is copyediting.
– A way to evaluate the scientific merit of an image…that is an
editor or reviewer’ role.
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– A way to evaluate whether an image is “ photoshopped”.
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3. Rapid Inspector: A preflight tool
What is Rapid Inspector?
– It’an application designed to ensure the quality and the
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accuracy of images of images submitted by authors.
– Help reduce time spent re-working digital art and quickly
detect and resolve any manipulations before production.
What does it do?
– Rapid Inspector equips users with a technical assessment of a
file and how it was built & it’characteristics.
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– It accepts or rejects images based on your criteria and
provides a list of errors with instructions for fixing them.
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11. File Formats
Graphic Formats designed for print
–TIFF
Acceptable Formats
–EPS
–PDF Peer Review only
Graphic Formats designed for www
–JPEG, GIF, BMP, PICT, WMF
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12. Industry Standard Editing Software
Adobe Photoshop (tif)
Best suited for editing images photos
Adobe Illustrator (eps)
Best suited for editing charts and graphs
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13. Pitfalls of Power Point
Color accuracy
PowerPoint files are intended for screen display (RGB color model).
CMYK color conversion is required for (commercial printing).
Poor typeface management
PowerPoint files can be opened with no warning that a font is substituted.
Thus, the font substitution is 'invisible' but very common and potentially bad.
Cross-Platform inconsistencies
Power Point presentations are not interpreted identically across platforms.
Graphics may be altered in appearance or not display at all.
Image format and resolution
PowerPoint does not have the ability to save high resolution tiff or eps files.
PowerPoint exports images using screen resolution, (72 dpi).
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14. Using PowerPoint Files
The best option is to copy images from
PowerPoint and paste into Adobe
Illustrator. This copy-and-paste method
will actually give you more predictable
results without resolution, font, and
quality issues.
Please see this tutorial available on the Cadmus Digital art site
http://cpc.cadmus.com/da/howto/creating_ai_eps_excel
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15. Vector Graphics
• Vector graphics are made up of mathematically defined lines and curves called
vectors. You can move, resize, or change the color of a line without losing the
quality of the graphic.
• Vector graphics are resolution-independent—that is, they can be scaled to any size
and printed at any resolution without losing detail or clarity. As a result, vector
graphics are the best choice for representing bold graphics that must retain crisp
lines when scaled to various sizes (logos, for example).
•Note: Because computer monitors can display images only on a grid, both vector
graphics and bitmap images are displayed as pixels on-screen.
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16. Bitmap or Raster Graphics
• Bitmap images—technically called raster images—are made up of a grid of dots
known as pixels. When working with bitmap images, you edit pixels rather than
objects or shapes. Bitmap images are the most common electronic medium for
continuous-tone images, such as photographs or digital paintings, because they
can represent subtle gradations of shades and color.
• Bitmap images can lose detail when scaled on-screen because they are resolution-
dependent, they contain a fixed number of pixels, and each pixel is assigned a
specific location and color value. Bitmapped images can look jagged if they’ re
printed at too low a resolution because the size of each pixel is increased.
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17. The 2 Worlds of Color
Transmitted Light Reflected Light
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18. The 2 Worlds of Color
• RGB exists in the
transmitted world of
light.
• Is a reality in computer
monitors and TV’ s.
• Suitable for internet
publishing at 72 PPI.
• CMYK exists in the
reflected world of light
utilizing pigments.
• Is a reality in all
printed materials.
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19. The 2 Worlds of Color
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52 99
Reflected Light Transmitted Light
“Perceived” “Actual”
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20. The 2 Worlds of Color
RGB Color Space
Visible
Spectrum Computer Monitors
Human Eye (soft proofing)
CMYK Color Space
Offset Printing
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22. Color Accuracy
Please do not rely on a monitor display to predict color
output on press. RGB colors on the screen are brighter
than what is printed on paper. Colors onscreen are
created with light, which adds brightness of its own to
the colors.
When printing on paper, the light is taken out of the
equation. RGB color can also be "out of gamut" for
CMYK printing, meaning that some of the colors cannot
be replicated with printing inks.
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23. Column width
A pica is printer's unit measure, equal
to 12 points or 1/6 of an inch.
Composition unit of measurement used
in determining the dimensions of lines,
illustrations, or printed pages.
1 column = 20 pica or 3.33 inches
1 1/2 column =30 pica or 5 inches
2 column = 41 pica or 6.833 inches
1 column 1.5 column 2 column
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24. Column Width & Sizing
Calculating Sizing Percentage: “
ideal for scanning”
The formula to determine resizing by percentage is to divide the target column width by
the original width. A 4x5 original intended for 1 column: 3.33” 4” 0.832” 83%
/ = or
Using rulers & guides to size:
To create a ruler guide: If the rulers are not already displayed, choose View > Show
Rulers. Position the pointer on the left ruler for a vertical guide or on the top ruler for a
horizontal guide. Drag the ruler guide into position.
To change the rulers' zero origin: Position the pointer over the intersection of the rulers
in the upper left corner of the window, and drag diagonally down onto the image. A set
of cross hairs appears, marking the new origin on the rulers.
Drag guides to the desired column width. With the selection tool, select the object or
objects to scale. Drag a handle until the selection is the desired size. Shift-drag the
handle to preserve the proportion.
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25. Line weight & Type
Fine Line Weights 100% Original
and Small Type Small Type
may be too small
after reduction
1/2 Point
1 Point
2 Point
4 Point
25% Reduction
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26. Line weight & Type Tips
Avoid using lines less than .5 Point
Panel labels should be 14 point Helvetica Bold
Type should be at least 9 pt at 100%
Submit Artwork final size that it will appear in
the journal (1 column wide, etc.)
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27. Adjusting Line Thickness
Using Adobe Illustrator
Under the Window pull down menu click on Stroke to display the Stroke
pallet if not already visible. Using the direct selection tool click to select
one of the thin lines. (see screen captures below)
Under the Select pull down scroll to Same and select Stroke Weight
With the all of the strokes with the same weight selected increase the
stroke value by clicking on the right arrow in the Stroke pallet and
selecting a greater value. As a general rule thin rules should not be less
than .5 pt.
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28. Shaded Area Tips
Use 20% Increments starting with 0%
Patterns fills can also be used instead of Shading
Shades of grey are preferred because they are most
compatible when copying and pasting into Illustrator.
Pattern fill’that are not compatible can be substituted
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using Adobe Illustrator preset patterns.
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29. Replacing Fills
Illustrator comes with a variety of preset
patterns. These patterns can be found on
the Hard drive and accessed by selecting
Window->Swatch Libraries->Other Libraries:
Typical location of preset patterns :
Local Disk(C:) ->Program Files->Adobe->Adobe Illustrator -
>Presets->Patterns->Basic Graphics
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30. Input Resolution
In order to print, we need to get:
From Here To Here
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31. Input Resolution
• Image files are
made from tiny
picture elements
known as pixels.
• Input resolution is
expressed in pixels
per inch (PPI).
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32. Input Resolution
300 PPI Image Resolution
• Formula for
determining
proper image
resolution: two
times the output
screen frequency.
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34. Output Device
An imagesetter is a high resolution
output device that can transfer
electronic text and graphics directly
to film or plates used in computer-
based preproduction work.
Unlike the resolution on a home or
office printer, which is probably
between 300 - 600 dots per inch
(dpi), the resolution on a typical
imagesetter is 1270 or 2540 dpi
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35. Output Resolution
Halftone Grid 15 LPI 150 LPI
Halftone screens are measured in lpi (lines per inch). This refers to how
many rows, or lines, of dots fit in a linear inch. The number of lpi in a
halftone screen is called the screen frequency or line screen.
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36. Resolution Summarized
300 PPI Image File
2400 SPI Imagesetter
Resolution
150 LPI Halftone
Screen Frequency
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37. Screens
• Binary system results
in an optical illusion
of tone gradation.
• Continuous tone
images are converted
to varying sized dots
in a grid pattern.
• This is known as the
“halftone” process.
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38. Screens: Dots a Moiré
• Uncontrolled variation
of grid placement
produces an
undesirable Moiré
pattern.
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39. Screen Angles
• Pre-set grid rotation
minimizes the effect of
Moiré.
• Grids placed at 45
degrees from each
other result in the
least amount of Moiré.
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40. Screen Angles
•Moiré avoidance requires
multiple screen angles
precisely placed.
•Dominant colors are placed
at greatest angles.
• degrees between
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dominant colors.
•Proper screen angling
produces a minimized
“rosette” pattern.
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41. Screens Summarized
Halftone screen attributes
include the screen frequency
and dot shape for each
screen used in the printing
process.
Setting the screens at
different angles ensures that
the dots placed by the four
screens blend to look like
continuous color and do not
produce moiré patterns.
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45. Fonts
Cadmus supports the use of the following
Type 1 PostScript fonts for the creation of
digital art figures:
•Times Roman
•Helvetica
•Arial
•Symbol
•European PI
•Mathematical PI
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46. Where to Get Help
Application Help
Adobe provides a variety of options for you to learn applications,
including online Help, and tool tips. You can easily access a host
of continually updated Web resources for learning Illustrator,
from tips and tutorials to tech support information using the:
Help menu
Cadmus Digital Art Web Site
http://art.cadmus.com/da/
Cadmus Email Support
digitalart@cadmus.com
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47. Digital Art Analysis
Digital Art Tools make Electronic Images a Dynamic Medium
Not all authors understand the Digital Art Tools they use
– Unintentional changes to images may result
– Data may be lost
– Data may be hidden
– Data may become confusing to interpret
Some authors understand the Digital Art Tools they use
– Proper image preparation may occur
– Images may be enhanced
– Images may be beautified
– Images may be altered, in the worst cases, fraudulently
Hwang et al., Science 303(5664): 1669-1674, 2004 brought
this issue to front page news
48. Digital Art Analysis
Most preventative steps are:
– Suitable for low volume workflows
– Rely on manual detection
– Require high-level Photoshop skills
– Are time consuming
– Catch those errors the human eye can see
The optimal solution is:
– Scalable
– Capable of integration into Peer Review workflows
– Robust, Fast, Easy to use
– Software-based detection: Rigour ™, JPEG Snoop
53. Digital Art Analysis –Quality Matters
For more information see: www.cenveo.com/pdf/digital_art_analysis.pdf
Contact Info: Chris Coleman, Digital Specialist, colemanc@cadmus.com
Greg Suprock, VP/GM, suprockg@cadmus.com
