ECI/bvdm Gray Control Strip • Manual • EN

Transcription

Gray Balance Control in Offset Printing
with the ECI/bvdm Gray Control Strip
Instructions for Use
June 2012
2 ECI / bvdm Gray Control Strip • Introduction
1 Gray Balance Process Control –
Easy, Practical, Effective
The aim of process control at press side is to quickly achieve the desired
color results. When the more important press parameters, such as standardized plate production, dot gain, paper and ink have been determined, then it won’t take very long to balance the inking for the best possible outcome.
The ECI/bvdm Gray Control Strip has been developed for printers as an
aid to help balance the press process in the best way possible by utilizing
a standardized proof. That’s why the ECI/bvdm Gray Control Strip is
based on the same color characterization data that are used in industry
standard ICC profiles (for example, the ECI profiles) and the Ugra/Fogra
CMYK Media Wedge in prepress. ECI offset profiles are based on color
characterization data from Fogra.
ECI / bvdm Gray Control Strip • Explanation 3
2 The ECI/bvdm Gray Control Strip
Gray balance patches that allow a quick and convenient visual control are
good aids for accurate inking. That’s why the “ECI/bvdm Gray Control
Strip” relies on this one simple rule: “Chromatic gray (CMY) has to look
exactly like true gray (K)”.
The aim is therefore, to match the ECI/bvdm Gray Control Strip chromatic
gray patches to the true gray patches by controlled inking. That is, the
technical tone consisting of defined cyan, magenta and yellow (chromatic
gray) values is compared to a tone value that consists of pure black (true
gray). By “balancing out” the colors at the press, two patches that consist
of two different sets of values ideally end up looking the same.
The Human Eye as “Metering Device”
Because the human eye is well suited in comparing colors that are
directly adjacent to each other, and in particular are very sensitive in
detecting color differences within the gray zone, they serve as a “visual
metering device” when using the ECI/bvdm Gray Control Strip for assessment. By visually controlling the gray balance patches, deviations in inking can be recognized and corrected in due time press side, before these
have a chance to show up on the printed image. Yet visually controlling
the gray balance in no way replaces a metered evaluation of full tone
color coordinates and the tone value increase or using an automatic color
control that may be on hand.
Why Gray Balance?
Standard process offset printing states that the correct dot gain for each
different printing ink is one of the most important preconditions for balancing printing and proof. It has also been determined that the difference
between the colors is not to be too great (key word: spread), or a deviation, for instance in the gray balance, may occur.
Usually the dot gain of each single process color is measured to verify this
stipulation. Even before a measurement is made, a color shift (e.g. a red
cast) in the chromatic gray patch when compared to the true gray patch
can be detected by simply inspecting it with the naked eye. Fundamentally, it is very useful to make an assessment based on screened mixed
colors (in this case the chromatic gray patch), since most images consist
of those tertiary colors. Print control elements that contain only screened
primary color values (no mixed colors) are not suitable for this type of initial evaluation.
4 ECI / bvdm Gray Control Strip • Explanation
“How Gray is Gray?” or “Which Gray Balance is the Right One?”
One approach in defining the most suitable chromatic gray patches
involves establishing exactly those CMY color value combinations from
out of respective color characterization data that match comparable values of pure black (true gray), and/or that arrive at exactly the same
CIELAB color values when metering the color.
The chromatic gray patches on the ECI/bvdm Gray Control Strip were
determined using this method. These correspond with the definition for
chromatic gray in compliance with the international press process standard ISO 12647-2: “A colour having the same a* and b* CIELAB values as
a half-tone tint of similar L* value printed with black ink.”. true gray 70
chromatic gray 70
true gray 50
chromatic gray 50
true gray 30
chromatic gray 30
ECI/bvdm Gray Control Strip (S) • FOGRA39 • v2
CMY 70
K 70
CMY 50
K 50
CMY 30
K 30
CIE L*
45,53
45,53
61,82
61,82
76,12
76,12
CIE a*
0,0
0,0
0,0
0,0
0,0
0,0
CIE b*
-0,75
-0,75
-1,16
-1,16
-1,52
-1,52
C
66
–
45
–
27
–
M
56
–
36
–
19
–
Y
56
–
36
–
20
–
K
–
70
–
50
–
30
Table 1: CIELAB color coordinates and CMYK values of true gray (K) and
chromatic gray patches (CMY) for offset printing on coated paper
(FOGRA39).
Respective characterization data for all printing conditions may be taken
from the CIELAB values for black. Characterization data are determined
by means of test targets (e.g. ECI2002 test table) that were printed on
specific papers under controlled conditions. These data also serve as a
basis for the creation of ICC profiles, which may be applied for data preparation and proofing.
Table 1 illustrates the CIELAB color coordinates and CMYK color values
of the three chromatic gray (CMY 70, CMY 50, CMY 30) and true gray (K
70, K50, K 30) patches for standardized offset printing on coated paper
(characterization data FOGRA39).
ECI / bvdm Gray Control Strip • Explanation 5
In printing, each chromatic gray and true gray pair look the same to the
human eye and ideally the color measurements show the CIELAB color
values from the characterizations file of the respective printing condition
(here: FOGRA39).
It is also important to make sure that the respective ECI/bvdm Gray Control Strip is applied according to the type of paper used, since different
CIELAB values of the black patches and different CMY values result
depending on the printing process and printing condition.
Definitions of the ECI/bvdm Gray Control Strip gray patches for offset
printing are each based on the Fogra characterization data for standardized offset printing in compliance with ISO 12647-2. The ECI produces
ICC profiles by means of these characterization data, which can be downloaded from the ECI website. They also constitute a part of the Altona
Test Suite Application Kit.
Fogra published new characterization data sets in June 2009: FOGRA45
for heatset web offset printing on improved LWC paper (light weight coating), FOGRA46 for heatset web offset printing on standard LWC paper
and for offset printing on uncoated white paper (FOGRA47). In January
2012 another characterization data set for web offset printing on INP
paper (improved news print) was added (FOGRA48).
A list of current versions and their classification according to paper type
can be seen in Table 2 on page 14.
6 ECI / bvdm Gray Control Strip • Explanation
Is Process Control of Other Printing Parameters Still Necessary?
The ECI/bvdm Gray Control Strip serves as an “early warning system” or
“quick test”. When a visual balance of true gray and chromatic gray on
the press is impossible to arrive at the conventional way, such as by a
change in the inking, this is an indication that some basic printing process parameters need adjustment. As a rule, deviations may be corrected
by changing influencing factors (i.e.: another ink, adjustment of CtP
curves). In order to locate and remedy the fault, it is required to review
the dot gain and full tone color coordinates of the inks and make an
assessment of additional areas (e.g. slur / doubling), which are typically
included in machine control bars. The ECI/bvdm Gray Control Strip is
therefore not a substitute for printing control elements, but rather a supplement to these.
Gray Balance – An ECI or bvdm Invention?
No! Gray balance is a known issue in the printing industry since decades.
Fogra covered the topic in many studies – the first was issued in the year
1953. In fact in printing the control of the gray balance has been in practice for many years, for example it is utilized in the “Ugra/Fogra Minitarget” (www.ugra.ch and www.fogra.org) and the density-based color control systems from System Brunner (www.systembrunner.ch). Simple
chromatic gray patches are still in common use in Scandinavian newspapers.
ECI / bvdm Gray Control Strip • Structure 7
2.1 ECI/bvdm Gray Control Strip Versions
The ECI/bvdm Gray Control Strip is available in three different layouts.
Depending on intended purpose and available space they can either be
applied singularly or in combination.
The Basic “S” Version
The ECI/bvdm Gray Control Strip “S” version consists of three true gray /
chromatic gray pairs. The true gray patches are arranged in 70%, 50%
and 30% tone values of the black ink. The tone values for cyan, magenta
and yellow in the respective chromatic gray patches were determined
from absolute colorimetric color conversions of CIELAB values (of the
respective black ink value).
Illustration 1: The Basic ECI /bvdm Gray Control Strip “S” Version
Two items are to be noted. Firstly, the CIELAB value of the true gray
patches originate from the corresponding characterizations file. Secondly, when determining the chromatic gray patches the black generation setting was “none” (without black ink).
The control element is 36 x 8 mm. Each patch is 6 x 6 mm. The identification line of the wedge allows you to verify the utilized printing conditions.
In this respect it is recommended to show the Identification line on the
printing forme.
The Expanded Versions “L”, “M” and “M i1”
The ECI/bvdm Gray Control Strip versions “L” and “M” are based on the
basic “S” version and contain additional patches for the measurement of
other process parameters.
ECI/bvdm
GrayCon L • v2
FOGRA39
Version “M”
ECI/bvdm
GrayCon M • v2
FOGRA39
cmy 70
Version “L”
cmy 50
k 50
cmy 30
k 30
cmy
cm
cy
my
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cmy 70
k 70
cmy 50
k 50
cmy 30
k 30
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my
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ECI/bvdm Gray Control Strip (M) • FOGRA39 • ISO 12647-2 gray balance condition ‘CIELAB black ink’ • Offset on gloss or matt coated paper (PT 1+2) • ISO 12647-2:2004/Amd 1 • Reference FOGRA39.txt (www.fogra.org) • www.eci.org, www.bvdm.org
ECI/bvdm
GrayCon M i1 • v2
FOGRA39
Version “M i1”
k 70
ECI/bvdm Gray Control Strip (L) • FOGRA39 • ISO 12647-2 gray balance condition ‘CIELAB black ink’ • Offset on gloss or matt coated paper (PT 1+2) • ISO 12647-2:2004/Amd 1 • Reference FOGRA39.txt (www.fogra.org) • www.eci.org, www.bvdm.org
cmy 70
k 70
cmy 50
k 50
cmy 30
k 30
Stop
cmy 70
Paper
k 70
my
cmy 50
cm
k 50
cy
cmy 30
cmy
k 30
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< Start
ECI/bvdm Gray Control Strip (M i1) • FOGRA39 • ISO 12647-2 gray balance condition ‘CIELAB black ink’ • Offset on gloss or matt coated paper (PT 1+2) • ISO 12647-2:2004/Amd 1 • Reference FOGRA39.txt (www.fogra.org) • www.eci.org, www.bvdm.org
Illustration 2: Expanded versions “L” and “M” with their density values
above each patch, identification lines below and an abbreviated version
on the left side of the wedge.
Layout “L”
The “L” layout is 291 mm wide and has a height of 10 mm, whereas each
patch (with exception of the last patch) is 5.5 mm wide. When necessary,
patch density values and the identification line below may be cut off so
that its height may be reduced to 6 mm.
8 ECI / bvdm Gray Control Strip • Structure
This layout consists of 51 control patches in all, which may be grouped as
follows:
Solid color overprint patches (trapping patches)
Paper-white
cmy 70
k 70
cmy 50
k 50
cmy 30
k 30
cmy
cm
cy
my
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ECI/bvdm
GrayCon L • v2
FOGRA39
ECI/bvdm Gray Control Strip (L) • FOGRA39 • ISO 12647-2 gray balance condition ‘CIELAB black ink’ • Offset on gloss or matt coated paper (PT 1+2) • ISO 12647-2:2004/Amd 1 • Reference FOGRA39.txt (www.fogra.org) • www.eci.org, www.bvdm.org
End patch
Gray balance patches
Halftone step wedges with primary color solid-tone patches
Illustration 3: ECI /bvdm Gray Control Strip patches divided into groups
– Start and end patch, required for positioning hand-held scanning
devices in front of the first measurable patch and for their phase out
after the last patch.
– Paper-white patch used as a reference value for densitometers and to
determine the paper color coordinate.
– Three gray balance patch pairs, consisting each of one chromatic gray
and one true gray patch for visual gray balance control. The true gray
patches are laid out in the tone values of 70%, 50% and 30%. The chromatic gray patches are created from out of the primary colors cyan,
magenta and yellow so that each printing condition indicated in the ECI/
bvdm Gray Control Strip identification line can ideally be visually
matched to the true gray patches.
– Solid color overprint patches (trapping patches), for the visual and
technical evaluation of secondary colors (M + Y, C + Y, C + M), also for
the tertiary color black (C + M + Y). This allows the detection of ink trapping problems.
– Halftone step wedges in the four primary colors: black, yellow,
magenta and cyan. Each halftone step wedge contains the tone values
from 10% to 100% in 10% increments. It serves for the visual (by way of
inking standards) and technical control of solid color inking and to
determine characteristic curves of printing.
Since it is often very hard to distinguish between neighboring control
patches, small white or solid-tone guide lines that border each patch and
that have no affect on the automatic measurement of scanning devices
were added to aid the positioning of the sensing head.
ECI / bvdm Gray Control Strip • Structure 9
Printing Conditions
The identification line below the patches contains the name of the control
wedge and the layout version (L). Following that are the printing conditions, a reference to the respective characterization file standard and the
gray condition in compliance with ISO 12647-2. The Internet addresses of
the project partners are also listed including those addresses where the
ECI/bvdm Gray Control Strip may be downloaded. Because the large version may be shortened to save space you will find at the left of the end
patch another three short lines with the abbreviated names and the reference name of the layout version, the wedge version (“v1”) and the characterization file name This information allows the easy identification of
each wedge.
Layout “M”
Layout “M” at a width of 197.5 mm is the abbreviated version of Layout
“L”. This version should only be applied when there is not enough available space on the paper format for the application of version “L”. This
can be the case for instance when short grain pages are to be processed
in A4 format.
Of course the 10 mm height of layout “M” may also be reduced to 6 mm
by cutting off the patch density values on the top and the identification
line underneath. The width of each control patch is 6 mm. Layout “M”
also differs from Layout “L” only by the number of the primary color halftone steps, where instead of 10% increments, 20% increments from 20%
to 100% tone values have been indicated.
Layout “M i1”
Between the patches marked “Start” and ”Stop“ the layout “M i1” contains patches for the fast measurement of CIELAB values and tone value
increase curves with scanning devices. Six gray balance patches for the
visual assessment have been added to the lower end of the control strip.
ECI/bvdm
GrayCon M i1 • v2
FOGRA39
cmy 70
k 70
cmy 50
k 50
cmy 30
Stop
k 30
cmy 70
Paper
k 70
my
cmy 50
cm
k 50
cy
cmy 30
cmy
k 30
100
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< Start
ECI/bvdm Gray Control Strip (M i1) • FOGRA39 • ISO 12647-2 gray balance condition ‘CIELAB black ink’ • Offset on gloss or matt coated paper (PT 1+2) • ISO 12647-2:2004/Amd 1 • Reference FOGRA39.txt (www.fogra.org) • www.eci.org, www.bvdm.org
Illustration 4: “ECI/bvdm Gray Control Strip (M i1)”
Layout “tvi 10”
The purpose of this control strip is the assessment of production prints
with regard to the specifications defined by the standard ISO 12647-2.
For that reason the strip contains solid-tone and overprint patches as
well as halftone steps in 10% increments. The “ECI/bvdm tvi 10” can be
used for all printing conditions as it does not contain graybalance
patches. The color sequence of the control patches is optimized for fast
measurments with scanning devices.
Stop
cmy
cy
cm
my
Paper
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ECI/bvdm
tvi 10 • v2
ECI/bvdm tvi 10 (i1) • 6 mm • Control strip with tone values in 10 percent steps for print process control in accordance with ISO 12647 • www.bvdm.org • www.eci.org
Illustration 5: “ECI/bvdm tvi 10”
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Start
10 ECI / bvdm Gray Control Strip • Application
Important Note Regarding Measurement with Scanning Devices
The space for control strips on printing sheets is very limited. For that
reason the control patches of the layouts “M i1” and “tvi 10” are smaller
than specified by the manufacturer X-Rite for the manual measurement
in scan mode using the ruler. Devices marked “Rev A” at the bottom side
are not suited for the measurement of these strips in scan mode. Using
i1Pro devices marked “Rev B”, “C” or “D”, in some cases errors in scan
mode measurements may occure – in particular on uncoated paper types
with an uneven surface or coarse screening. All revisions (Rev A-D) will
work properly if mounted on the iO scanning table. In order to achieve
reliable measurement results it is recommended to measure the same
control strip in the modes “strip” and “patch” and to compare the two
results. In the case of significant differences choose the reliable “patch”
mode and do not use the ruler.
3 Implementation of the ECI/bvdm Gray Control
Strip
Which ECI/bvdm Gray Control Strip Version Should I Use?
In order to make the right selection for the correct wedge to use, you have
to consider the printing conditions (see also Table 2 on page 14). Aside
from this, there are three different layout versions available per printing
condition. This allows you to choose the most suitable version according
to the amount of space available.
Example: A matt-coated paper (paper type 2) is intended for the final
printed product. The matching Fogra characterization data is identified
as FOGRA39. If there is enough room available on the paper, the “L” or
“M” expanded version should be utilized. This will allow a visual check of
the gray patches as well as a technical measurement of the characteristic
printing curves. In this case use the “ECI_GrayConL_FOGRA39.pdf”
wedge. If there is only very little available space, the basic “S” version
identified as “ECI_GrayConS_FOGRA39.pdf” should be used. The basic
“S” version is key for the visual control of a press run.
How is the ECI /bvdm Gray Control Strip Positioned?
All the different versions of the ECI/bvdm Gray Control Strip are available
as PDF files. Choose the version that best suits the printing conditions and
position the ECI/bvdm Gray Control Strip for instance in your imposition
program as a supplement to your usual control aids. In work environments that do not allow PDF files, the EPS version of the wedge, for example “ECI_GrayConL_FOGRA39.eps”, may be applied. Make sure that the
printing condition in the identification line that this wedge represents is
still discernable.
cmy 70
k 70
cmy 50
k 50
cmy 30
k 30
cmy
cm
cy
my
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ECI/bvdm
GrayCon M • v2
FOGRA39
cmy 70
k 70
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k 50
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k 30
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07
07
20
03
001
05
08
08
my
04
01
05
09
09
cy
05
02
06
001
001
cm
06
03
04
01
01
cmy
07
04
02
02
k 30
08
05
07
03
03
cmy 30
09
06
03
04
04
k 50
001
07
08
05
05
ECI/bvdm
GrayCon M • v2
FOGRA39
ECI/bvdm
GrayCon M • v2
FOGRA39
ECI/bvdm
GrayCon M • v2
FOGRA39
ECI/bvdm
GrayCon M • v2
FOGRA39
ECI/bvdm
GrayCon M • v2
FOGRA39
ECI/bvdm
GrayCon M • v2
FOGRA39
08
02
06
06
cmy 50
09
09
07
07
k 70
001
01
08
08
M
S
03 k 03 ymc 05 k 05 ymc 07 k 07 ymc
ymc
mc
yc
ym
01
02
03
04
05
06
07
08
09
001
01
02
03
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
mdvb/ICE
2v • L noCyarG
93ARGOF
04
05
06
07
08
09
001
01
02
03
04
05
06
07
08
09
001
01
02
03
04
05
06
07
08
09
001
tvi 10
L
S
001
09
09
cmy 70
tratS
001
001
ECI / bvdm Gray Control Strip • Application 11
The basic version “S” should be at right angles to the printing direction,
for example placed below the color bar you normally use. A repeated
placement enables a color balance assessment.
The two expanded versions “M” and “L” as well as the “ECI/bvdm tvi 10”
must be positioned between the pages at right angles to the gripper edge;
wedges positioned parallel to the gripper edge would distort the dot gain
calculation of unavoidable inking deviations between the ink zones.
Under some circumstances the analysis of the wedge may be distorted on
account of atypical inking behavior when it is placed at the edge of the
paper.
mdvb/ICE
2v • 01 ivt
mdvb/ICE
2v • 01 ivt
Illustration 6: Placement of the “S”, “L” and “tvi 10”version on sheets with
long cut-off pages. The red X marks unsuitable positioning.
Illustration 7: Placement of the “S” and “M” version on sheets with short
cut-off pages. The red X marks unsuitable positioning.
100
12 ECI / bvdm Gray Control Strip • Application
What Can be Done when K-Gray and CMY-Gray Patches do not Match?
In principle, the standardized offset printing process in compliance with
ISO 12647-2 and/or “ProzessStandard Offsetdruck” (bvdm 2001, 2003)
guidelines is to be instituted. Target values and tolerances are itemized in
the “MedienStandard Druck 2004” (download of current version at www.
bvdm.org).
When however the chromatic gray and true gray patches do not correspond, try adjusting the inking and damping control of one or more of the
process colors to arrive at a good match.
Example: a) When the chromatic gray patch has a red cast when compared to the true gray patch, decrease the magenta and yellow inking or
increase cyan.
b) When the chromatic gray patch is too light when compared to the true
gray patch, increase the CMY primary inks or reduce true gray.
It is to be noted that the gray balance patches only illustrate a bias. In
order to find out whether the primary color inking is to be reduced or
increased you must make an additional assessment of other control bars,
for example check the halftone wedge of the “L” or “M” version of the
ECI/bvdm Gray Control Strip.
In some circumstances deviations arise that do not allow themselves to be
corrected by adjusting the inking. Let us take for example the following
case: The 50% patch is acceptable, but the 30% is not chromatic. The
characteristic printing curve of the entire tonal gradation is not balanced.
Initially you have to rule out any printing faults (for example slur / doubling, gradual fading, etc,).
Then it is absolutely essential that a characteristic printing curve with a
sufficient increase in tone value is created throughout (for example by
means of the expanded ECI/bvdm Gray Control Strip “L” version). A calculated correction of the CtP system may become necessary as a result of
the findings.
It should also be noted that there are a multitude of possible causes for
printing problems, for instance in connection with the materials being
used (paper, ink, blanket, additives, etc.). The bvdm ProzessStandard Offsetdruck extensively describes possible causes and gives trouble-shooting
instructions. The Altona Test Suite Application Kit documentation
describes pre-tests to determine the most optimal inking and the correct
tone value increase.
ECI / bvdm Gray Control Strip • Remarks 13
Gray Balance Remarks
It is well known that with process inks in offset printing, inking and
damping fluctuations show up more distinctly in chromatic gray image
areas than in colored image areas. This is why gray balance patches in
color control bars have been instrumental in the indication of printing
process disorders. Gray balance control should be carried out allowing
for the following constraints.
On the one hand it depends on the prevailing printing conditions, for
instance the type of paper or the screening which tone value combination
of primary colors (cyan, magenta, yellow and black) result in an actual
chromatic gray in the print. Most of the control aids available up until
now (for example the Fogra control strips) have only one single version of
the gray balance scale. In conventional film / plate making, managing a
large number of control strips coordinated to all the different printing
conditions would have been extremely inconvenient and would probably
have presented a potential source of trouble. Still, gray balance deviations in the print run can be well detected with the aforementioned control aids. By comparing the gray balance patches on the o.k. print and
print run sample, fluctuations can be easily detected despite the inaccuracy of chromatic gray balance patches. Today thanks to automated
workflows it is easy to display control aids on full-page films or printing
plates that match the intended printing conditions.
On the other hand, the gray balance is dependant on printing parameters
that are influenced by at least these four factors: the dot gain, the solid
color inking of the primary colors, overprinting and paper color. A gray
balance control alone can therefore not give any information about any
potential cause for errors and in itself does not allow an assessment for
recommendations at the press. Now as ever screened patches of the primary colors, solid color and solid color overprint patches are required in
color control bars. This also applies to automated control systems that
function according to the gray balance control principle.
The gray balance of the o.k. sheet are reference for the process control of
the entire print run – even if the respective chromatic gray patches are
not perfectly neutral.
A color cast in the chromatic gray patches of the ECI/bvdm Gray Control
Strip not neccessarily indicates the same color cast in gray tones of
images. In particular dark image areas contain a significant amount of
black ink. This minimizes the color cast caused by the chromatic inks
cyan, magenta and yellow.
14 ECI / bvdm Gray Control Strip • Versions
4 The Different ECI/bvdm Gray Control Strip
Versions
ECI and bvdm offer free versions of the ECI/bvdm Gray Control Strip for
the most important offset standard printing conditions. These are labeled
by name (file name, identification).
Printing condition
Characterization data
Profile file name
ECI/bvdm Gray Con Strip
Offset, Paper type 1+2
Gloss and matt coated paper
Tone value increase curves A (CMY) and B (K)
FOGRA39
ISOcoated_v2_eci.icc
ISOcoated_v2_300_eci.icc
ECI_GrayConS_FOGRA39
ECI_GrayConM_FOGRA39
ECI_GrayConM_i1_FOGRA39
ECI_GrayConL_FOGRA39
Offset, Paper type 3
new 2009
Improved LWC paper (Light Weight Coated)
Tone value increase curves B (CMY) and C (K)
FOGRA45
PSO_LWC_Improved_eci.icc
new 2009
Standard LWC paper (Light Weight Coated)
FOGRA46
PSO_LWC_Standard_eci.icc
new 2009
Uncoated paper, white
Tone value increase curves C (CMY) and D (K)
FOGRA47
PSO_Uncoated_ISO12647_
eci.icc
Uncoated paper, yellowish
FOGRA30
ISOuncoatedyellowish.icc
Offset, SC paper
Super calandered paper
FOGRA40
SC_paper_eci.icc
Offset, MFC paper
Machine finished coating paper
FOGRA41
PSO_MFC_Paper_eci.icc
Offset, SNP paper
Standard newsprint paper
FOGRA42
PSO_SNP_Paper_eci.icc
Offset, Paper type 1+2
Gloss and matt coated paper
Non periodic screening, 20 µm
Tone value increase curve F (CMYK)
FOGRA43
PSO_Coated_NPscreen_
ISO12647_eci.icc
Uncoated white paper
Non periodic screening, 30 µm
Tone value increase curve F (CMYK)
FOGRA44
PSO_Uncoated_NPscreen_
ISO12647_eci.icc
ECI / bvdm Gray Control Strip • Versions 15
Printing condition
Characterization data
Profile file name
ECI/bvdm Gray Con Strip
Offset, INP paper
improved newsprint paper
FOGRA48
PSO_INP_Paper_eci.icc
ECI_GrayConS_FOGRA8
Table 2: Available versions of the ECI/bvdm Gray Control StripOther Printing Conditions
As above listed ECI/bvdm Gray Control Strips cover the most important
standard offset printing conditions these versions should be used.
Upon request ECI will create special versions of the ECI/bvdm Gray Control Strip for publishers of characterization data and profiles available on
the ECI website.
As an exception the opportunity is available to create your own versions
corresponding to special printing conditions. For this purpose ECI and
bvdm offer InDesign documents free of charge for the four “S”, “M” and
“L”versions of the ECI/bvdm Gray Control Strip. These InDesign documents along with a manual are located in the folder “Custom” which is a
part of the download package.
Characteristics of the new Version 2
In version 2 of the ECI/bvdm Gray Control Strip, two bugs have been
fixed, which may occure when creating PDF files or when printing documents containing the previous version of the “GrayCon”: moved other
page content, moved characters in the info text on the control strip, such
as the numbers above the patches.
The ECI, bvdm and Fogra recommend the immediate use of version 2 in
order to avoid these problems. The adjustments have no impact on the
measurement of the control strips as neither the layout nor the color
values have been changed. The version is indicated by “v2” in the file
name and on the control strip.
16 ECI / bvdm Gray Control Strip • Imprint
5 Imprint
Publisher:
European Color Initiative (ECI)
c/o Olaf Drümmer
callas software gmbh
Schönhauser Allee 6/7
10119 Berlin, Germany
www.eci.org
German Printing and Media Industries Federation (bvdm)
Biebricher Allee 79
65187 Wiesbaden, Germany
www.bvdm.org
© 2009 ECI and bvdm
The ECI/bvdm Gray Control Strip and the ECI/bvdm tvi 10, ECI/bvdm Control Strip in the following, are freeware and are available at the publisher’s Internet addresses shown above for download. You may use the ECI/
bvdm Control Strip at your own discretion for as long as you want, on as
many computer workstations as you need and in whichever country you
wish. However it is not permitted to distribute the ECI/bvdm Control
Strip, to change or modify it, in whole or in part, without written permission from European Color Initiative (ECI) or the Bundesverband Druck
und Medien (bvdm). You may use the ECI/bvdm Control Strip at your own
risk. The publisher is not to be held liable for any errors or resulting damages that may arise, during or after ECI/bvdm Control Strip use. We do
not provide support and services. If you should require help in using the
wedge, we recommend seeking advice from relevant Internet fora, such
as the ECI mailing list (see www.eci.org).
ECI / bvdm Gray Control Strip • Contributors 17
6 Contributors
The following persons have cooperated in the development of the
ECI/bvdm Control Strip:
Michael Adloff (Conzepke Software Service GmbH & Co. KG, Monheim am
Rhein) Harry Belz (bvdm, Wiesbaden) Dr. Günter Bestmann
(Heidelberger Druckmaschinen AG, Kiel) Wolfgang Brügelmann (Druckzentrum Köln West Druckerei Peipers GmbH, Köln) Sascha Bugai (Lean
Produktion GmbH & Co. KG, Hamburg) Dieter Dolezal (Hirte MedienService GmbH & Co. KG, Hamburg) Olaf Drümmer (callas software GmbH,
Berlin) Axel Faber (MediaTailor GmbH, Hamburg) Bernd-Olaf Fiebrandt
(Verband Druck und Medien in Baden-Württemberg e.V., Ostfildern)
Kurt Fuchsenthaler (Heidelberger Druckmaschinen AG, Heidelberg)
Dr. Johannes Hoffstadt (GMG GmbH & Co. KG, Tübingen) Jan-Peter
Homann (homann colormanagement, Berlin) Andreas Kraushaar (Fogra
Graphic Technology Research Association, Munich) Steffen Kujus (REWEZENTRAL AG, Köln) Karl Michael Meinecke (bvdm, Wiesbaden) Roland
von Oeynhausen (Otterbach Medien KG, Rastatt) Prof. Ronald Schaul
(Stuttgart Media University (HdM), Stuttgart) Ulrich Schmitt (Fogra Graphic Technology Research Association, Munich) Florian Süßl (zipcon consulting berlin GmbH, Berlin)

ECI/bvdm Gray Control Strip • Manual • EN

Transcription

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