Colours In The Cloud – Print Validation

This article is reproduced with permission
Colours In The
Cloud – Print
print buyer in focus, which has several implications for
their design and architecture. A key element is that the
reporting of measurements is normally done to a central
server – hence the term ‘Colours in the Cloud’.
Bodoni pressSIGN
This is a UK-based software developer with significant
success world wide, founded in 1990. The company
became involved in colour management at the turn of
the century when it started to import high end scanners
from Denmark and needed to ensure the monitor was
correctly calibrated, leading to a long history of applied
colour management. Early on Bodoni adopted the use
of international standards in print workflows and is
authorised by FOGRA to do PSO certifications. Of late it
has complemented this with pressSIGN certified to the
GRACol G7 by IDEAlliance. The G7 System is the preferred
way to calibrate printing presses to be in compliance to
the American printing standard GRACoL – similar but
still slightly different from the FOGRA method for press
calibration. On top of its own software solutions, Bodoni
We have already presented some colour management
solutions the cloud theme in Spindrift, including
Colibri from Matchmycolor, and ColorDrive by
Schawk. Recently we covered RapidCheck from
Tucanna, and this time we will look at pressSIGN
from Bodoni and PrintSpec from Mellow Colour.
What these software programs all have in common is
that they haven’t been developed by any press or CTP
manufacturer. There are colour management solutions
from vendors like Agfa, Fujifilm, Heidelberg, Komori,
ManRoland and others, but these are mainly aimed at
the printer or prepress house. But the software that
we’re considering in this series of reviews largely has the
The scoring system in Bodoni pressSIGN, summarised here in the green box to be 87%, makes it easy to quickly evaluate if a print run
has passed. More detailed information is available for a deeper analysis.
© Digital Dots Ltd •
This article is reproduced with permission
standard of how to define them, especially gradations. The
VLT Technology (Visual Linear Technology) calculates
when, for example, a 50% tint is perceived as having half
of the lightness of solid ink.
also distributes a range of colour management related
software, devices, colour targets etc.
There are four versions, or levels, of the pressSIGN
software. The complete suite of modules is included
in what is called pressSIGN Global Print Management.
This includes reporting to a cloud-based central server,
as well as all of the other modules for press control and
softproofing. Bodoni uses a scoring system for print
validation and evaluation and, depending on what
parameters are included such as the use of spot colours or
Those users that don’t need or want the complete system
can choose between three other configurations, where
the pressSIGN Pro V6 contains all the press calibration
tools, including spot colour libraries, but doesn’t use
cloud-based technology for reporting.
One step below this version is pressSIGN V6, typically
suitable for digital print production or litho offset with
just one or a few presses. Finally, there is the pressSIGN
PrintBuyer V6, and as the name indicates, it is mainly used
for print validation, not press control. In this version the
print buyer can monitor and validate print production
according to all the established industry standards
including ISO 12647, GRACoL, JapanColor etc.
There are four versions,
or levels, of the pressSIGN
software. The complete suite of
modules is included in what is
called pressSIGN Global Print
All of the pressSIGN versions support a wide range
of spectrophotometers, including most models from
manufacturers like Barbieri, Konica Minolta, Techkon
and X-Rite.
not, different weighting is applied so that the maximum
total score is always 100%. The user can determine what
score is to be regarded as a Pass or Fail, but typically this
is set to be 80%. This is not identical to a strict validation
to for example ISO 12647-2, but can be modified so that
a score of less than 80% roughly means that you fail to
comply with ISO 12647-2 for offset printing.
Mellow Colour Print Spec
As is the case with Bodoni, Mellow Colour is also
UK-based, but has successfully implemented its solutions
and training services worldwide. PrintSpec is just one
of the modules in its suite of software, but perhaps the
most well known from the company. The principle used
by Mellow Colour is that every installation to a client is
regarded as a unique configuration, based on customer
But Bodoni doesn’t stop at checking for compliance to
standards – it also helps printers to correctly calibrate
the presses and printers, and improve the print quality.
For example its 4CX (4 Colour eXchange) technology
helps printers achieve correct and neutral grey balance,
while the NPD (Neutral Print Density) function helps
with adjusting a digital press to perform visually to target
values based on TVI (dot gain), which have no direct
equivalence in a digital press.
This means that there are no pre-defined sets of
configurations, but instead all of the modules available are
mixed for a client based on their specification. Alongside
PrintSpec there are other modules in the mix, like InkSpec,
FlatLine, ImpressionProof, LinkSpec and MellowCloud.
Since it’s important that any changes to compensation
curves can be executed by the RIP system creating
the plates, pressSIGN is compatible with and can
communicate with all of the major RIP systems on the
market. Spot colours, often used as brand colours, are
traditionally difficult to manage, since there is no ISO
On top of offering software, Mellow Colour also performs
what is called Gap Analysis as a preparation for a printer
aiming to be certified according a certain print standard.
This can be according to the certification scheme
© Digital Dots Ltd •
This article is reproduced with permission
Mellow Colour also uses a scoring system, summarised in the green sphere in the bottom right corner. The modular approach is
indicated by the additional functions showing in the pull down menu under the active module.
setup by BPIF (British Printing Industries Federation),
which combines ISO 12647 and other ISO graphic arts
standards with ISO 9001 for general quality management.
But printers that have shown consistent compliance to a
certain standard can also be certified to what Mellow
Colour calls the ISO 12647 Proficient Printer scheme,
similar to the BPIF and FOGRA PSO schemas, but not
authorised by any of those. Printers certified to this
program are listed on the Mellow Colour website, which
to date numbers about a hundred sites worldwide.
operator tries their best to keep the density across the
ink zones as close as possible to the aim values. When a
press is correctly setup and maintained, the indicator bars
follow a straight flat line across the monitor, ensuring
density is neither too high anywhere, nor too low either.
While we still talk about and use density for press control,
in reality we use a spectrophotometer in order to not only
calculate density, but also get the spectral values needed.
This is important both for printing with process colours
like CMYK, but especially when using spot colours. Colour
deviation is calculated as Delta E (∆E), and depending on
which standard you try to comply with, there are different
tolerances for how high a ∆E you can accept. The values
read and analysed by FlatLine are then fed into PrintSpec
or the other modules used.
PrintSpec is commonly used in most configurations of
the Mellow Colour press control and validation system,
however the FlatLine module is necessary for almost
any measurement made. The term indicates the typical
user interface for press control systems where the press
© Digital Dots Ltd •
This article is reproduced with permission
In PrintSpec a scoring system is used to evaluate how
well a print conforms to a set standard, and typically
a threshold of 80% is selected for a measured sheet to
pass. This scoring system is one of the validation options
accepted in the certification schema managed by the BPIF,
and can be set up exactly to mirror this. But validation can
be done to other print standards as well, like GRACoL and
Another module is InkSpec, which manages special
colours, typically spot colours. But this also helps with
managing inks used in the process colours CMYK.
Combining conventional measurements of ∆E, TVI (dot
gain) and density, InkSpec also supports the use of spectral
data. This is very important when communicating with
ink formulation software, to achieve the best possible
match to a specified brand colour.
Finally, the MellowCloud makes it possible to share
measurements across sites and for a print buyer to validate
print runs remotely. The reporting is similar to PrintSpec,
with either a summary of what score was achieved or a
detailed report. It’s also possible to perform statistical
analysis and trending – all in all supporting a systematic
approach to print quality!
Both the Bodoni and Mellow Colour solutions have several
things in common – they don’t only analyse and validate
if a print is within set tolerances – they can also help the
printer re-calibrate or adjust the press or printer to come
within tolerances. And they have an easy enough user
interface for a print buyer to evaluate the print quality of
the contracted printers, even remotely. In addition they
are available in both Mac and PC versions, another factor
that makes it easier for publishers and print buyers to use
them. This is all very impressive!
– Paul Lindström
© Digital Dots Ltd •