Decreasing metamerism of inkjet printed wood grain

Vinay Anil Turke¹, Paul D. Fleming², Veronika Husovska³ and Alexandra Pekarovicova²
E-mails: vturke@proedgefilms.com; dan.fleming@wmich.edu; v.husovska@pressburgllc.com; a.pekarovicova@wmich.edu
¹ ProEdge Inc., 23326 Shelby Road, Shelby, IN 46377
² Center for Printing and Coating Research, Western Michigan University, 4601 Campus Drive, A-217 Parkview, Kalamazoo, MI 49008
³ Pressburg, LLC, Kalamazoo, MI 49008

Abstract

Today, the competitive environment in the graphics communication industry is demanding the printer to produce good quality products within short periods of time. To ensure quality reproduction of print jobs, prototyping is necessary. Rotogravure cannot be used for prototyping, because of high manufacturing cost of gravure cylinders. Such challenges can be successfully tackled by use of relatively cheap and flexible printing processes, such as inkjet. Even though inkjet printing is a cost-effective way for prototyping, it has its own limitations, especially in the case of wood grain printing. Wood grain patterns need to be printed with a release coating and adhesive. Inkjet printers are incapable of printing either release coating or adhesive, because they require a certain amount of coat weight, not possible to deliver with inkjet printing. Inaccurate color reproduction, metamerism and incompatibility with release coat are the commonly seen problems during inkjet prototyping. The main aim of this study was to resolve problems such as metamerism and close color match of inkjet and gravure printed wood grain. A design of experiments (DOE) was carried out by using different factors such as gray component replacement (GCR) settings, release coat weight and use of tie coat to analyze their effect on metamerism. Custom created ICC profiles decreased the metamerism index (MI) and ∆E*_ab significantly, when compared with the generic RIP printer profile. Manual GCR adjustment in addition to custom created ICC profiles decreased MI further, but at the same time increased ∆E*_ab to some extent.

Increased GCR settings had considerable impact on MI, which varied per color shade. The ICC profiles for the 7 g/m² release coat plus tie coat and 10.5 g/m² release coat plus tie coat substrate were created with 160 % total ink limit values, whereas 7 g/m² release coat and 10.5 g/m² release coat samples without any tie coat were profiled with 180 % and 200 % total ink limit, respectively. Higher total ink limit samples on 10.5 g/m² release coat with no tie coat showed
the highest color gamut volume and lowest total ink limit, while 7 g/m² release coat plus tie coat showed the smallest color gamut volume. ANOVA statistical analysis showed that GCR setting was the most influential factor on MI followed by the use of the tie coat. Release coat weight was an insignificant factor for MI.

Keywords: inkjet, rotogravure, metamerism, color match, gray component replacement

JPMTR 098 | 1708 Research paper
DOI 10.14622/JPMTR-1708
UDC 774.8|7.026-0353

Received: 2017-08-24
Accepted: 2017-10-25

Comparison of ICC and DNG colour profile workflows based on colorimetric accuracy

Jure Ahtik
E-mail: jure.ahtik@ntf.uni-lj.si
University of Ljubljana, Faculty of Natural Sciences and Engineering, Snežniška 5, SI-1000 Ljubljana, Slovenia

Abstract

Managing colours is important for every photographer. In this paper, two of the solutions were described and researched: ICC colour profiles and DNG colour profiles. While ICC is a well-established and commonly used option, there are some disadvantages when it comes to time, price, and understanding; DNG colour profiles offer us a good response to these disadvantages but as a result the quality of colour corrections is lower. This paper gives the exact answers on how big the colour difference between both processes is and what the cases are when the use of ICC or DNG colour profiles is advised. The main focus of the research is a usability of both workflows.

Keywords: digital photography, colour management, colour reproduction, colour test chart, white balance

JPMTR 099 | 1710 Research paper
DOI 10.14622/JPMTR-1710
UDC 535.6|7.021|77.067

Received: 2017-10-11
Accepted: 2017-10-30

A study on Facebook and WhatsApp during Chennai floods 2015

N. Bhuvana and I. Arul Aram
E-mails: br.mediastudies@gmail.com; arulram@yahoo.com
Department of Chemistry, Anna University, Chennai-600025

Abstract

In December 2015, unexpected floods occurred in Chennai, which was officially declared a disaster city, and was puzzled as to what Nature had for it next. The then isolated city had all its sources of communication cut, except access to Facebook and WhatsApp through mobile phones that enabled timely update on flood news and weather forecast, a way to connect with family and friends to ensure safety, putting out SOS signals and listing out worst-affected areas that needed volunteering and basic items such as food, water and other relief to the citizens. Chennai has 3.5 million (35 lakhs) Facebook users browsed through a smartphone. Likewise, WhatsApp is used as the top smartphone app by 96 per cent of people in India. Various features of it went viral in spreading information which brought food, clothing, shelter, support and love from all ends of the globe. Apart from individuals, non-governmental organizations (NGOs) and other stakeholders also used both Facebook and WhatsApp actively during the crisis. This paper aims to provide a better understanding of how NGOs used Facebook and WhatsApp to engage with the victims during Chennai floods 2015. The results revealed that Facebook was used by NGOs to reach out the public for getting help in the rescue, relief and rehabilitation for the victims. Whereas, WhatsApp was used by various organizations, police officials and volunteers to communicate with them once on the field and also off the field. With respect to residents of Kotturpuram, the use of WhatsApp for the above set indicators seemed more timely during Chennai flood 2015 than Facebook. The usage of these communication media had turned the citizens as activists and made them take control over the situation and bounce back to normalcy during Chennai floods 2015.

Keywords: citizens, disaster management, Kotturpuram, social media

JPMTR 100 | 1707 Case study
DOI 10.14622/JPMTR-1707
UDC 659.3(255)

Received: 2017-08-18
Accepted: 2017-10-31