Supporting "good enough" colour reproduction in non colour managed workflows

In this paper we propose a novel and coherent approach to control and adjust colour reproduction where strict end-to-end colour management cannot be achieved. We first recall the studies and findings that identified the need to reconsider colour management in certain workflows. We then present in detail the Print Mediator system, constituting a first attempt to implement this new approach. Introduction In some digital printing industry workflows the adoption of state of the art colour management approaches to solve the problem of colour reproduction across various displays and printers has failed due to practical constraints. This has been reported as relatively common in studies of graphic design for products and marketing where documents are created by design agencies but ultimately printed by separate print shops (cf. [1,2]). In this paper we present a practical alternative to strict end-to-end colour management in the digital printing industry. This work is the outcome of several in-depth work practices studies (see [5] for an introduction to this research method) of print workflows conducted in order to better understand the barriers to adoption of colour management [2,3,4]. Our suggestion does not replace but rather complement existing colour management approaches which are themselves based on sound scientific groundings. This paper is structured as follows. In the first section we briefly expose the findings of the work practice studies that motivate our approach. We highlight the causes for the failure of traditional colour management approaches that these studies identified in various settings and describe the current practices used by professionals in the absence of a colour managed workflow. We also explain how these studies have driven the design of our approach in complementing existing traditional colour management. The second section then presents the design of the Print Mediator system, being our first attempt to address the highlighted weaknesses. Here we describe in detail the features of the proposed system. In section 3 we discuss how Print Mediator differs from existing techniques and technologies and why we believe it proposes a novel and coherent approach to control and adjust colour reproduction where strict end-to-end colour management cannot be achieved. Finally we conclude by presenting some preliminary tests and indicating some future work to be done to further validate the proposed concept. Motivations Colour profiles and International Colour Consortium (ICC) protocols are meant to enable colour to be rendered consistently across devices. They embody formal colour management procedures. These protocols and techniques rely on rigorous mathematical models and have facilitated the design of very sophisticated and accurate colour reproduction technology. Whilst the use of colour management has proved its efficacy in certain application domains, [1] found that about two-thirds of design firms and publishers do not use colour management at all and that, where they do, the print shop personnel often do not trust the colour expertise of the designers, and discard any profiles included in the document. Our more recent field studies have confirmed these observations. As discussed in [2] one of the weaknesses of colour managed workflows is that they need to be applied end-to-end, i.e. rely on good practices at all steps of the document creation-to-printing process in order to produce valid results. Additionally problematic from a printers’ perspective is that while they understand colour profiles in files are often an artefact of choices unwittingly made by designers, they have no clear way to recapture what the ‘real’ intent of the document was. Thus, when the lack of consistent industry standard colour management practices in everyday workflows results in problematic colour output this leads to an increased time-to-press and requires several print iterations before adequate print results are reached. Furthermore, such workflows require a high amount of communication and collaboration between print shops and customers to sort out colour problems, and are therefore less suited for the emergent short-run, ondemand, web-based printing needs. Rather than the underlying technical principles of colour management what is challenged here is its adoption in some workflows. For this reason, we felt that a deeper understanding of the professional practices in these settings was required in order to understand the barriers preventing the adoption of colour management and to get some insights in how to better support it. We carried out our research through multi-sited ethnographic work practice studies (cf. [5]) in Europe, the US and Canada of print shops and graphic design houses. Ethnographic workplace studies have been used in computer systems design in fields like HumanComputer Interaction (HCI) and Computer Supported Cooperative Work (CSCW) since the 1980s (cf. [6,7,8,9]). They are a social scientific method that involves the gathering of qualitative data, in situ, in field-sites, through observation (and note taking), unstructured interviews and video and audio recordings and the analysis of how work is organised as a recognisable social accomplishment. A better understanding of the application domain and the way technologies are used and understood collaboratively, within e.g. a workflow, can be helpful in reconfiguring those technologies or providing inspiration for technology innovation. The study highlighted a serious miss-match between the concerns, activities and understandings of many designers and the way colour management controls are instantiated. Colour management technology can be thought of as a technical infrastructure supporting colour reproduction across different rendering devices of a workflow. Our studies indicated a knowledge and interest gap in the industry (i.e. colour management is too complicated for the average user to understand, and is furthermore not a central concern during the design activity). As such it would need to be controlled by a “colour engineer” with specific knowledge and concerns about administration of overall colour reproduction across the devices of the workflow [3]. In many small and medium sized teams and cross-organizational settings, having a skilled person dedicated to this function constitutes too much of an overhead and the responsibility for managing colour (i.e. working to get good enough colour rather than adhering to colour management, profiles etc.) is thus shared across the different actors and organisations producing the documents. ‘Successful’ colour management would ideally start with document designers. However, designers have a very different approach to colour compared to a colour management expert. They deal with colours primarily as they perceive them, on screen or onprint. Furthermore, they are aware of colour reproduction problems and operate with tolerances that relate to aesthetic concerns (does it look good, is the design harmonious), customer requirements (what is important, what will they accept, how much money can they spend) and also the lack of perceptual constancy between successive viewings (they do not always notice colour changes). For example, the green colour of the grass in a photo might be allowed to change as long as it appears somehow natural, while the green colour of a company logo would need to be pretty exact. In contrast to such a tangible and practical object related colour definition, colour management involves the manipulation of global colour space mappings, with very accurate and objective definitions but it is disconnected from specific instances of the design and from their requirements, tolerances and so forth. Designers do not master the underlying principles of colour management. They do not grasp the links between the colour management controls and the effects on their particular design. This often leads to inappropriate and incorrect use of colour management technology. From our study we have identified a strong incompatibility between the way document designers interact with colour and the way colour management needs to be monitored. This does not mean, however, that document designers underestimate colour reproduction issues and the need for colour management. They rather engage in very ad hoc colour management practices based on a practical understanding of colour reproduction issues and ad hoc strategies to palliate them (see also [3,4]). They are often built on the basis of well established relationships and collaborations between designers and printers. These practices include printers providing specific swatch books to theirs customers, doing colour tests, or defining dedicated spot colours in printer libraries for a recurrent customer. Also, ‘savvy’ designers work systematically in a CMYK colour space during design to be “close to the printer”. These practices can be seen as neither systematically optimal nor scientifically correct but they all have the advantage of offering to their users a more graspable (and realisable) way to handle colour in their work. The currently available more robust colour management solutions, in contrast, lack this graspable dimension. To improve their design and increase their adoption it is therefore important to carefully consider the observed current practices. From the study two main directions have emerged to improve the colour reproduction in settings where strict colour management is not affordable. The first one is to rethink the interface between the colour management infrastructure and the document producers in order to help them in choosing the appropriate options and improve the quality of their documents through better colour specifications. The second one is to acknowledge that the communication between the designers and printers will remain central to solving the colour reproduction issues when documents have not been designed and handled prop