Six degrees of separation: A look at the hexachrome™ high fidelity color reproduction system by Scott Fry for Professor Dan Wilson A broadening of the gamut of 46). A hi-fi color reproduction Q&A, 1998, p. 1–4). The addi- reproducible process colors system dates back to 1972, when tion of these two colors to the would be welcomed by the print- it was devised by Harald Küpper. reproduction process allows ing industry. The quest for better His theory was to increase the Hexachrome to exceed the RGB process inks have been a step in printable gamut by using cleaner spectrum in all but the green area the right direction but still has ink pigments and adding orange, of the spectrum (see Figure 1.1). not produced “perfect” inks. green and violet. This system was Through this system, offset With the advent of extra-trinary researched by German ink man- printers can now reproduce col- color separations (more than ufacturers who developed the ors beyond the gamut of the three primary colorants) printers Küpper colorant set. Other high monitor and even into the fluo- have been exploring the possibil- fidelity systems, like the Davis rescent and pastel range ( Jeffrey, ities by which colors gamuts Hi-Fi Color Project, use CMYK 1995 p. 46). In addition to this, could be expanded (Lamparter, +RGV inks to expand the color Hexachrome can accurately re- 1994, p. 52–3). The Hexa- gamut (Lamparter, 1994, p. 53). produce 90% of all PANTONE chrome™ system from PAN- A system by DuPont, called spot colors, compared to the 55% TONE® has offered one viable HyperColor, uses only CMYK of matches available from con- solution for printers who want to inks to reproduce an image. ventional CMYK process (Wil- expand their color capabilities. However, HyperColor achieves son, 1995, p. 31). This package, consisting of a few its expanded color gamut by software plug-ins, plus a calibra- increasing ink film density. Installation of Hexachrome tion program, will allow printers “Bump plates” are added to to reproduce a broader color printing units to print additional To produce Hexachrome sepa- space with only minor changes in layers of ink in one or all four rations, the minimum desktop prepress workflow. colors (Whitcher, 1998, p. 70). requirements are a PowerPC or The term hi-fi color (short for PANTONE introduced Hexa- 68040 or better Macintosh, high fidelity color) was coined by chrome in 1994. This color Adobe Photoshop 3.0 or later, Don Carli as a comparison to reproduction system takes the and a page layout application high fidelity stereo equipment, basic CMYK inks, reformulates capable of placing a DCS 2.0 which reproduces sound with lit- them, and adds green and orange file. As it currently stands, tle distortion ( Jeffrey, 1995 p. inks to the process (Hexachrome PANTONE only manufactures this Visual Communications Journal 1999 Page 49 The hard drive contains the ity would be lost due to gamut HexWrench folder, which con- clipping (Hexachrome Q&A, sists of a PDF manual and the 1996, p. 4). Changing the color third piece of the puzzle: Hex- space of an image from RGB to Wrench Tuner. This is the cali- CMYK can result in a 25% brator of the system. After print- reduction in color range (Whit- ing a control swatch, measure- cher, 1998, p. 70). No special ments can be taken from each alterations are necessary during Figure 1.1. Hexachrone color patch with a ColorTron or the image manipulation process. gamut Spectroline colorimeter to create Color casts, sharpening, and all an ICC profile, which Hex- other image correction tech- Wrench then uses to create sepa- niques are unaffected by system for the Macintosh plat- rations. The result of this calibra- Hexachrome (Hexachrome Q& form (Studion Soft, 1996, p. 2.4). tion is what HexWrench uses to A, 1996, p. 4). Three main components are determine dot gain compensa- Once an RGB image is ready loaded during the installation of tion (Studion Soft, 1996, p. 6.2- to undergo separation, pulling the PANTONE HexWrench soft- 6.10). down the “filter” menu and going ware. First loaded is SAME to “color” will initiate the Hex- (Studion Appearance Matching Hexachrome workflow Wrench plug-in. Here a control Environment), a control panel window appears, displaying the which acts like a color manage- With these software elements image and the settings for creat- ment tool for the purpose of in place, the Hexachrome work- ing separations (see Figure 1.2). compensating color differences flow can begin. Scanning and This is where the user may select between input devices, output image capture can be performed wether they want to create an devices, and monitors (Mac as usual, but all images must image screened at 175 lpi, 200 World, 1998, p. 46). remain in RGB space. If images lpi, 14µ or 21µ stochastic. The Second loaded is HexWrench, were to be transformed into user also selects coated or un- which consists of two Photoshop CMYK at any point, their viabil- coated paper and adjusts the total plug-ins. These plug-ins are what allow the six-way separa- tion to occur. The biggest advan- tage that these plug-ins offer is the ability to control the separa- tion process. Users can select image segments and alter the separation settings and then view the effect via soft proof. Dif- ferences between coated and uncoated paper, total ink limit, screening and even CMYK vs. Hexachrome can all be proofed on screen before any separation takes place (Studion Soft, 1996, p. 5.1–5.14). Figure 1.2. Creating separations with Pantone HexWrench Page 50 Six degrees of separation ink limit (which PANTONE calls er controls are available regarding creating separations in Hex- the black modifier). Information the nature by which the images Wrench. This is the only way about the origin of the image is will be separated (Moretta, 1998, that dot gain compensation can also specified. HexWrench in- p. 6-8). occur. By reading the test patch- quires as to the nature of the es with a ColorTron or Sepectro- original media, reflection or Proofing concerns line colorimeter, the profile will transmission and which scanner be built and incorporated into profile captured the image, Proofing systems are available the SAME list of profiles allowing SAME to compensate for Hexachrome, but mainly in (Studion Soft, 1996, p. 6.2– for color variation. analog form. Agfa, Dupont, Fuji, 6.10). Profiles are also requested After the settings have been and TransCal are the major sup- in making separations from changed to their correct posi- pliers of proofing materials for QuarkXPress 4.0 and any other tions, a set of separations are the Hexachrome System (Hexa- Hexachrome compatible soft- generated by clicking the “sepa- chrome Q&A, 1998, p.4). ware that integrates color man- rate” button. After the separation Digital proofs can be made to agement directly into the appli- process is complete, seven files simulate Hexachrome output. cation (Anderson, 1998, p. 12). will appear on the desktop. Six of Some digital color output devices these files are color channels and have a gamut that is over 50% Press considerations one file is a DCS 2.0 that can be greater than conventional process placed into almost any page lay- color work. For example, the When someone uses the term out application (Studion Soft, gamut of the Scitex Iris proofing “hi-fi color,” the thought of a six- 1996, p. 5.1–5.14). system for example, encompasses color press printing stochastic With the release of new appli- almost all of the Hexachrome screens comes to mind. With this cation versions that support gamut, making it an acceptable scenario comes some serious Hexachrome, a less complex digital proof for hi-fi color press concerns. While many workflow is available. While (Andersson, 1998, p. 21). The printers assume that stochastic image capture and manipulation Epson Stylus Pro 5000 can also screening is used exclusively for still follow the same procedures, be used to create Hexachrome hi-fi, this is not the case. Hex- rather than creating separations proofs. Both of these printers can achrome repeats two of the out of Photoshop they are made give designers an idea of what screen angles to eliminate a upon output from a page layout the printed result will look like. moiré pattern with conventional application. With Hexachrome However they are not considered screens. Orange is printed at the supported software, RGB images a contract grade proof (Whit- same angle as cyan. Green is can be placed directly into the cher, 1998, p. 70). printed at the same angle as application. Once placed, pro- magenta (Whitcher, 1998, p. grams like QuarkXPress 4.0, Hexachrome calibration 69). Adobe PageMaker 6.5, Corel Another substantial concern Draw and Macromedia Free- HexWrench Tuner is a stand- to experienced lithographers is hand 7.0 will automatically cre- alone application that produces how to control the total ink limit. ate separations. The advantage of ICC profiles for presses. The cre- To print a total possible 600% this workflow is that the user is ation of a profile is critical to ink film would represent a nearly required to perform fewer steps. producing good Hexachrome impossible task with the mark- However this is also the work- separations. The profile for the ing, picking, curling, and drying flow’s disadvantage because few- target device is asked for when difficulties that would occur. Visual Communications Journal 1999 Page 51 Unfortunately, this is a weakness low pigment, but with the addi- gies, like stochastic screening and of Hexachrome. The black mod- tion of fluorescent pigments.