iccMAX – new color management system

Posted: December 5, 2016 in Color

iccMAX

ICC color management meets the goal of creating, promoting and encouraging the standardization of an open, vendor-neutral, cross-platform color management system architecture and components. While the current architecture works well in many areas, new potential applications are emerging and it is believed that tomorrow’s color comunication will require a more flexible and extensible system. ICC has developed a new specification, iccMAX, that will address many of these new requirements.

It is important to note that iccMAX is not intended as a replacement for ICC v4, the existing architecture, but as an extension or alternative where requirements cannot be fully met by v4.

What is iccMAX?

iccMAX is a new color management system that goes beyond D50 colorimetry. This new specification has been approved by the ICC Steering Committee.

iccMAX profiles show v5 in the header to distinguish them from v4 and v2. iccMAX profiles also have class, sub-class, versioning and header information that differs from v4.

Users and developers are encouraged to make comments on the specification.

Backwards compatibility

iccMAX provides a significant enhancement to the functionality of the current v4 specification. It is recognised that in many industries, v4 (and even v2) meets existing color management needs and in these industries there will be no drive to move to adopt the new specification.

An iccMAX CMM will be completely backward-compatible and will recognise and correctly process v2 and v4 profiles. However, iccMAX profiles are not expected to be compatible with v4 CMMs. ICC has provided a reference implementation to help with iccMAX adoption (see below).

How will iccMAX profiles be different?

The main changes you can see are:

Profile Connection Space

The ICC v4 PCS has fixed D50 colorimetry, considered necessary until now to ensure interoperability and prevent ambiguity in colour transforms. iccMAX allows flexibility in the selection of illuminant and color matching functions. It supports spectral communication of colour information through an optional spectral PCS, and also supports the use of color appearance processing in the PCS, with the facility to store appearance attributes in a v5 profile.

Support for extended CMM functionality

A variety of new types of information can be stored in an iccMAX profile to support run-time transform creation of a smart or dynamic CMM. Examples include:

  • a new gamut boundary description (GBD)
  • support for spectral data
  • measurement data using the CxF format
  • a new encoding of Named colors to support tints

Programmable transforms (e.g. direct encoding of device models) are supported through Multi-processing Calc elements, with functional operators, conditional evaluation, persistent variables and vectorized operations for improved performance.

Future extendability is also provided through support for hierarchical data encoding, allowing optional data to be added later without requiring changes to the tag parser.

Abbreviated profiles

CMMs are able to select or define a suitable transform by referencing the color encoding standard (such as those listed in the ICC Three-component Registry) which can be specified in a v5 profile in place of a complete transform.

Source: www.color.org

The iccMAX specification is now available to download on the Specifications page.

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Spot Color Inclusion mechanism (SIM)

Posted: December 5, 2016 in Color

Spot Color Inclusion mechanism (SIM) for printing with 3 color process inks and spot color replacing black as fourth process color.

Wiki Defines Spot color as below

“In offset printing, a spot color is any color generated by an ink (pure or mixed) that is printed using a single run.” And it defines the CMYK color model (process color, four color) “as a subtractive color model, used in color printing, and is also used to describe the printing process itself. CMYK refers to the four inks used in some color printing: cyan, magenta, yellow, and key (black). Though it varies by print house, press operator, press manufacturer, and press run, ink is typically applied in the order of the abbreviation”.

Generally the cost and potential for problems for a print job increase as one adds more spot colors, due to the increased cost and complexity of added process inks and plates, and requiring more runs per finished print. However, because of the complicated process, spot colors are effective at preventing forgeries of money, passports, packaged products, bonds and other important documents. Money printing for example, uses secret formulae of spot colors, some of which can be seen by the naked eye and some that can only be seen by using special lights or applying certain chemicals.

In today’s competitive market, all the packaged products are printing spot color as part of their job work. Let’s see a below image as an example

Figure 1: Image courtesy : www1.macys.com

In the above mentioned image, the image is with process CMYK colors and background is with pantone Reflex blue C.

For a typical printer in India who is having a 4 color printing press, these jobs will involve printing the job in two passes thus increasing the production cost by double. In the price competitive market, this erodes his margin as he has to fight to keep these kinds of packaging jobs in hold against a competitor who is having a 5 color printing press.

So there is an urgent need to support these printers with pre-press tools so that he can do the printing in one-pass. One option is to convert the spot colors in to process color combinations of C, M, Y, K percentages which will give the equivalent color perception.

For ex: a pantone blue can be printed with c=90% m=83% and black=10%.

But this method is prone to issues of color variations and color in-consistency.

So there is a need for some other tools to make the printing efficient and hence the tool of “Replacing a process color with Spot color without compromising print and color quality”. Hence the method of “SIM” is developed.

Procedure:

1. The process color and spot color combination in the printing job to be evaluated to understand which color can be replaced.

2. In the example shown above figure 1, the spot color used is Pantone Reflex blue. This leads to two possibilities of removing process colors and replacing it with process color. Either we can replace the Cyan with Pantone Blue or the black can be replaced with the pantone color.

3. A Hybrid test form (Chart 1) is printed to determine the best possible density for the spot color mentioned in the job. The density is determined on the basis of Hybrid Model Approach” (HMA)

4. The test chart is specially designed with a continuous wedge of solids along with dot gain patches. The sheet is printed with different densities from one end to other end. The variation is kept at 0.05 densities.

5. The wet densities were measured and sheets are allowed to dry. After 8 hours, the ‘Lab’ and ‘Print Contrast’ are measured on each density patches.

6. A curve depicting different lab and contrast values are generated. The lab values are compared with customer job specified standard lab values. It is observed that most of the cases, Delta E with medium deviation and maximum print contrast are matching.

7. Instead of choosing the lowest Delta E density, if we choose the point where both “print contrast” and “medium deviation Delta E”, the print results are better.

8. To evaluate this a ECI 2002 test chart is printed with the possibilities

a. Normal CMYK Printing

b. Pantone blue, M, Y, K process printing (replacing with Cyan)

c. C, M, Y and Pantone blue process printing (replacing with black)

9. Then these charts are measured with Heidelberg Color Tool box to understand the gamut of the above mentioned ECI 2002 test charts. It is observed that ECI test chart with option “C” closely suited the gamut required in the job.

10. A “Device-link” profile is created with the characterization data obtained from the ECI test chart.

11. A new dot gain curve is created to compensate the effect of Pantone blue over cyan and magenta regions. This dot gain curve is also obtained from the test chart.

12. Using image conversion software, the image is then converted to the destination profile with pantone blue elimination black color.

13. The job is then printed with C, M, Y, Pantone Reflex blue with compromising the use of pantone colors and print quality.

14. The printing quality is compared with 4 color + Process color printing and decided to make the analysis by human perception. The same sheets are given to “10 Standard Observers” and their visual assessments are compared.

15. Interesting the standard observers were not able to identify noticeable difference in print quality and they perceived it as usual CMYK + Spot color printing.

Further Scope:

The SIM system can be improved with an automatic mechanism to identify the image and recommend the right replaceable process color and corresponding “device link profile” and dot gain curve accordingly.

Chart 1

Prelude:

Out of 2, 50,000 printing presses in India, more than three-quarter of them are small-sized printers (SSP) venturing in low value commercial printing segment. These printers are in mystic enterprise world, in which value of their each useful resource is growing, but margins are dwindling thanks to price war in addition to challenges of new technologies and digital economy. It is not a feature Indian print market alone, similar trend is observed globally.

An inclusive and frugal innovation is required to address this complex trivia. It is not about the next big thing, but about making the most of the last big thing. Gandhian Engineering & Indovation will be the key to survival in this complex market.

What is Gandhian Engineering (GE)?

Embracing Mahatma Gandhi’s ideal of “doing More, for Less, for More, (MLM)”, it aims to democratize technology with Affordable Excellence – Giving high quality at affordable prices! It breeds a new kind of innovation coined as Indovation: “Spend less and innovate.”

Optimal utilization of resources & raw materials are key areas to focus in Indovation.

Indovations for small printers segment:

1. 29” Press or 26” Press? Best of both?

Most of Indian/Asian jobs are printed in demy size (19 x 26 inches) or double demy (25 x 36 inches). But for ganging jobs like visiting cards & invitation etc., a 29” press is required. Even though we can a print a 26” (inch) job on a 29” (inch) press, difference in plate size increases cost by more than 5%.

Indovation is to “Change the ink & water forme rollers of the press to 26”(inch) size to use 26”(inch) plate itself thus reducing overall print cost by 3%. When printer requires bigger size (29” inch) to be printed, replacing ink & water forme rollers will suffix. On an average, this increases printer margins by 10% with increased job capability.

Figure 1: By changing roller 12 & 6 to 26", printer can save plate cost

2. Printing trim waste paper with double gripper jobs:

Most B3 presses can run a minimum paper size of 4” (inches) x 6” (inches). When trimming papers for Demy (19 x 26” inches) from 30 x40”inches paper, there will be wastage of 4 x 20”inch. These wastage papers are sold in 30% of paper cost in kilos

By imaging a printing plate with two different jobs like below, in a B3 size press, the customer can print first job in 4×20” for a typical visiting card, invitations imposed for this paper size.

After completing first job, same plate is dismounted and fitted for the second job (gripper edge interchanged). Thus it reduces cost of printing plate for one job and also reduces paper cost by 70%. It is known as “Cutting bits to Commercial Prints”. It increases profitability by 33% in average.

3. Printing in 3 Colors

For a typical commercial printer with a 4 color press, printing 5 color job needs two print passes and hence reduces his competitiveness against printers with 5, 6 color presses. So utilizing the ancient printing technique of converting a CMYK job – CMY using designing software like corel draw will help printer complete the job in one pass. Printing in 3 color means doesn’t compromise the print quality. A very close simulation and quality towards 4 colors can be achieved by proper color management techniques.

This method has been tested and successful in entry level packaging jobs like fireworks boxes and garment jobs. It increases profitability by 16% in average.

Figure 3: A typical garment job, where a 4 color CMYK image will be printed in 3 color CMY combination without compromising print quality

Conclusion:

Indovation in commercial print is a true win-win combination of ‘excellence’ and ‘application’ together. It gives printers ‘affordable excellence to thrive on the powerful combination of scarcity and aspiration. Most of the described Indovations has been tested in real market conditions and getting successfully utilized by the printers.