GMG ColorServer

Colour is a notoriously tricky area to get right, says Barney Cox, but GMG's ColorServer has managed to iron out many of the usual inconsistencies



 


 


Colour has always been a complicated issue and something of a sacred cow too, demanding love and attention from the experts to get it right. That's all changing now as the black art of colour control succumbs to automation and the adoption of standards just like so many other craft-based skills that have gone by the wayside.

With more and more firms looking to adopt printing specification ISO 12647, the award has highlighted the importance of matching the right CMYK separations to on-press performance. Not all CMYK is created equal - even if it's intended for the same printing conditions - and a different CMYK breakdown may pass muster on proof, but prove a problem on press.

At its most basic, ColorServer has a part to play in ironing out those inconsistencies by standardising separations. That makes a minder's life much easier as they can be sure that, if a sheet has got images from a mix of sources, all have been rebuilt to behave consistently - meaning that when the ink keys are adjusted, there are no surprises and less compromises to get the best overall result.

ColorServer's ability to separate from RGB to CMYK, or reseparate CMYK-to-CMYK and to map spot colours to the available gamut of any printer or press, isn't just a tool for printers. It is equally useful in a large studio preparing output for many different print processes, or a repro house tailoring work for output in different publications, geographies or processes, as it is at a printer taming inconsistent separations and optimising the output from different machines to produce consistent colour across them.

RIP compatability
In the 4.6 version of ColorServer, there is extra power to make it simpler to use and more suitable for today's businesses, which are likely to have multiple print processes and machines that all need colour matching. The product has also become more than just a colour control tool. The incorporation of the Adobe PDF Print Engine (APPE) into ColorServer provides the ability to control the PDF version it outputs and to flatten transparency, which can help ensure compatibility with older RIPs and alleviate the need for additional investment elsewhere in the workflow.

"Not only is there a colour management benefit, there's also a cost-saving benefit because you don't need to upgrade all your RIPs," says GMG UK technical sales consultant Simon Landau. It simplifies the workflow with new hot folder-based functionality that makes it possible to support multiple presses and printers, and to keep then all calibrated.

"Before it was a hassle to match multiple devices, so we developed SmartProfiler," adds Landau. "Now, you can calibrate from the hot folder, and more importantly it opens up the software to anyone, even those with little colour skill."

With ColorServer and SmartProfiler, it is a simple process to characterise any output device, but especially digital presses and wide-format printers that may use additional colours to the standard CMYK set, such as an orange, green or violet or light cyan, magenta and black. In fact, SmartProfiler was developed to make the product more suitable for the digital and wide-format markets. And it's not just about characterising different devices, it's possible to characterise how different substrates interact with any printer or press to ensure consistency across a range of media.

For any application, where supplied jobs have special and spot colours, it is simple to reseparate to get the best possible match based on the colour gamut of the output device using the built-in Pantone library. It also simplifies the handling of colour, as all the colour management is done in ColorServer. "I've seen a lot of RIPs in my time and none can handle colour as powerfully as ColorServer," says Landau.

ColorServer developed out of a product called CamFlow, which was designed for separating RGB tiles from digital cameras into CMYK. In practice this didn't find much favour as it was a niche product and putting separation into the hands of the photographers turned out to be less than ideal, as they didn't really understand what they were getting into. So the product evolved into a colour workflow tool capable of doing RGB-to-CMYK and CMYK-to-CMYK conversions for standardising colour.

At the heart of ColorServer are the tools that GMG uses in ColorProof to produce contract-quality proofs on inkjet printers. These include its MX3 and MX4 files, which describe the colour gamut and reproduction of each device, and which are used for the colour calculations. These data files can be fine-tuned using the Colour Value Correction (CVC) tool. This gets right to the heart of GMG's approach and allows fine-control of critical colours using a colour manager's expertise and judgement rather than just the numbers produced by a spectrophotometer. "The CVC enables individual control of the colour values to make proofs match the press sheet," adds Landau. "The three- and four-colour greys - especially in the highlights - are where people are most sensitive to variations."

So, although the software uses colour theory to automate many processes that used to rely on a skilled retoucher-come-colour manager, it also acknowledges the shortfall of a purely numerical process and provides a best-of-both-worlds approach that uses human skills for tweaking results more accurately to be embedded in an automated workflow. "Just getting the delta Es down is not enough - you need to use colour tools sympathetically to what you want to achieve and to provide a colour match," says Landau.

Unlike most colour tools out there GMG opts for ICC technology for its colour processing in favour of its proprietary 4D colour processing technology, which it claims is the key to its success in being able to provide results that measure up. "It's a proprietary technology, but can work within an ICC workflow if it needs to," explains Landau. "However, most people don't use ICC once they've installed GMG."

At the heart of the 4D technology is the understanding that ICC-based approaches do not necessarily protect the purity of each colour separation. Working in the Lab colour space disregards the separation, which can destroy the black channel and introduce problems in the primaries and secondaries.

Range of new features
Another new feature of version 4.6 is improved gamut mapping, which is how the software will produce reproduction on a machine and substrate combination where there is a smaller available range of colours than is assumed in the supplied file. "It uses an intelligent mix of colorimetric and perceptual techniques, which is better than most retouchers for CMYK-to-CMYK; it's awesome," says Landau.

One area that often goes hand-in-hand with separation optimisation is ink optimising, where the software rebuilds the separation to minimise the use of coloured inks by substituting black where possible to save on ink usage with the attendant cost and printability benefits. ColorServer itself isn't an ink optimisation tool, but GMG does offer a separate standalone product InkOptimizer, which can be used alongside ColorServer, including running on the same hot folder in an automated workflow.

The product comes in several versions, depending on what suits your needs. All include profiles for common output colourspaces such us the Fogra 39L characterisation of ISO 12647-2, but if you need to create custom profiles to describe a non-standard space you need the Pro version, which includes profile editing.

SmartProfiler is available in a bundle with ColorServer, and is intended for firms with multiple printing technologies so, if you're a purely litho printer, it's not necessary, but if you have any digital machines, or multiple digital or wide-format printers, it is necessary to ensure the best output from each machine. GMG also offers a version of ColorServer as a service. It's not a hosted online service - GMG supplies a server for the software that is installed on your premises, but you rent the system monthly, and keep the package and any profiles GMG has created for you at the end of the term.


SPECIFICATIONS

Price

ColorServer Standard (no profile editing) £5,750,
ColorServer Pro (includes profile editor) £8,225,
ColorServer Bundle Standard (includes SmartProfiler) £7,400,
ColorServer Bundle Pro (includes SmartProfiler and  profile editing) £9,890,
Process Control Bundle (ColorServer Pro plus InkOptimizer Sheetfed £12,750
ColorPro Platinum Service from less than £1,000 per month (two-year contract)

Platform Windows XP or Vista

Contact GMG UK 01603 789111www.gmgcolor.com


THE ALTERNATIVES

Alwan Color Expertise CMYK Optimizer

CMYK Optimizer is based on ICC profiles. However, it has its own set of tools that allows the user to preserve the purity of primary and secondary colours, achromatics and overprints. Alwan argues that its Dynamic DeviceLink technology and colour quality assurance tools make it unique.

Platform Mac or PC

Price €5,990 (£5,423)

Contact Alwan Colour Expertise +33 4 7216 0882 www.alwancolor.com


CGS Oris PressMatcher Pro

As with ColorServer, PressMatcher also uses a 4D transformation space, but it can operate in an ICC environment too. The Pro version supports PDF and hot folder operation, while the more basic Web version outputs to PostScript printer drivers.

Platform Windows Server, XP and Vista

Price PressMatcher Pro: £7,990; PressMatcher Web: £4,300

Contact CGS 07894 057616 www.cgs.de


Heidelberg Color Carver and PDF Toolbox

While profile creation and editing are carried out in Prinect Color Toolbox, which supports CMYK and multichannel separations, Heidelberg offers two tools for separation: separation standardisation and ink optimisation Color Carver, which is included as part of Prepress Manager; and a standalone Acrobat plug-in called PDF Toolbox, which applies transforms pre-RIP as is designed for small printers running B3 and B2 presses.

Platform PC

Price PDF Toolbox £775

Contact Heidelberg UK 0844 892 2010 www.heidelberg.com

 

Kodak ColorFlow

Kodak highlights its ‘sexy' interface and its colour relationship manager, which tracks and accounts for any changes to the colour settings anywhere within the workflow. ColorFlow can be used standalone or integrated with Prinergy with flexible options about at what point in the workflow to apply colour management.

Platform PC

Price not supplied

Contact Kodak 020 8424 6514 www.kodak.com


Targetcolour MPX 360 Colorserver

Based on ColorLogic's Zepra transformation technology and Targetcolour's clever profiling techniques, MPX 360 ColorServer is claimed to offer unequalled transformation quality in an ICC environment. It also goes beyond CMYK to support up to 16 colours in a PDF workflow, making it appealing to both packaging and digital applications.

Platform Mac or PC

Price £4,995

Contact Targetcolour 0800 999 0990 www.targetcolour.com