Teaching Printing Process Control by Colorimetry
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Bob Chung, RIT rycppr@rit.edu
Wuhui Liu, Wuhan University wuhui_liu@163.com
IGAEA Annual Conference
July 22-26, 2007, Rochester, New York
Teaching
Printing Process Control
by Colorimetry
Topics
Introduction (5 min.)
Printing process control (15 min.)
Color measurement demo (15 min.)
X-Rite 530 with ToolCrib
X-Rite DTP 70 with ColorPort
Using On-Site Excel templates (10
min.)
Q/A (5 min.)
Teaching Printing Process Control by Colorimetry
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Introduction
Printing has been transformed from craft to
science.
Print buyers demand quality.
Color measurement devices are affordable.
Modern process control techniques are matured.
Standards-based printing becomes the norm.
Industry level, e.g., SWOP, GRACoL, SNAP
International level, e.g., ISO 12647
Introduction
Printing specifications are about aim points and
tolerances.
Colorimetry-based specifications are replacing
density-based specifications.
Parameters used in densitometric conformance
• SID and tonal value increase
• ∆D and ∆TVI
Parameters used in colorimetric conformance
• ∆E tolerance of CMYKRGB solids
• TVI tolerances
proof
aimpoin
t
X
Teaching Printing Process Control by Colorimetry
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Motivation
Print buyers demand a total solution from
content creation to prepress to printing.
Publishing and packaging
Here and around the world
Digital color management integrates prepress
and press together.
Device characterization requires colorimetry.
Standard-based printing by colorimetry becomes
the trend.
There is a need to learn how to teach standard-
based printing by colorimetry in school
curriculum.
Curriculum Emphases
1. Verify that the correct process inks are used
2. Adjust the ink amount to conform to
colorimetric aim points
3. Exercise process control
Status T density & TVI (CGATS.4)
∆E & metric chroma (CGATS.5)
4. Document printing conformance of the press
run by sampling
Teaching Printing Process Control by Colorimetry
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Equipment and Materials
Ve