A Class on Colours
IFTA comes up with the second edition of workshop on colour management
The India Flexographic Technical Association (IFTA) organized a hands-on workshop on Colour basics & Measurement at the J J School of Arts, Mumbai from November 14-15, 2008. The purpose was to help its members as well as the people from the flexo industry with the knowledge on the scientific and the technical aspects of colour and its application.
Day 1
“Lack of knowledge is the mostcommon
reason of failure in any industry.If you are unaware of the colour basics and the ways of their measurement, you can never succeed in inventing newapplications,” said Kiran P. Prayagi, Partner, Graphic Arts Technology & Education, starting the first session on the colour basics- light, colour and human vision.
Giving a detailed presentation on the science of colour, human perception and application, he marked the difference in eye to eye verification of colours. He gave an insight into the applications of ‘cone’ and ‘rod’ in the human eye. Referring to the recent research on the colour blind people, he said, “The ratio of colour blind men as compared to women is 80:4. This shows that the female eye has larger possibilities of acceptance of different shades of colours.”
Professor Ranjan Joshi, Graphic Designer and Visual, took over the dais to edify students on the faithful or false reproduction of colours and effects of various substrates on visual appearances of colours.
Enriching the students further with the detailed explanation of colour reproduction in printing, colour monitors and photography, Prayagi spoke about the colour reception from prints. “The most common method of colour presentation, in television as well as several other applications, is based on reception. Any combination of two colours might show you one colour (out of those two) as an outcome or may be a third colour. The result depends on what your eye accepts and what it rejects,” explained Prayagi.
Sharing his comments on the first day of the workshop, Nishanth Sukumar, Packaging Development Officer, Cadbury India Ltd. said, “It is not just about learning the colour basics, but the indepth knowledge on colour management and measurement that has added value to my attending this workshop.” “The handout of presentations that had been given to us in advance helped us make notes on the slides for future reference,” he added.
Day 2
The second of the workshop started with a presentation on CIE system. (Commission Internationale de l’Eclairage - International Committee on Illumination). “CIE's standard for measuring color is based on how the human eye perceives it,” asserted Prayagi. He further gave a brief on the device dependent/independent colour, colour matching functions and colour terminology.
Throwing light on the specifications of LCH and LAB measurement methods, Prayagi said, “In the LCH system, a colour is specified by three co-ordinates – L, C and H. Similarly in LAB, it is done with the L, A and B measurement angles.” “Though the applications may vary, the principal is same in both the cases,” added Joshi. Prayagi further guided students on the colour difference, Delta-E forlulae and the colour gamut.
“LAB and LCH had been my area of doubt as I could not distinguish their applications. Through the session I have learnt about these measurement techniques and their functional areas. Besides, the practical sessions stood helpful in understanding the specifications of measuring equipments,” said Pradip Raj, Quality Manager, Selyeget.
The two day workshop concluded with a vote of thanks to IFTA and the eminent speakers. “We are glad our efforts could help the students find answers to their doubts. This is our second edition of workshop after Pune and we promise to organize more of such events in the near future,” assured Maruti Shanbaug, Executive Secretary, IFTA.
Practical Sessions
Practical sessions were carried both on the Day 1 and Day 2 of the workshop helping students with the densitometry and colourimetry measurement techniques. Under densitometry, measurements were carried on colour densitometer (T6CR) and Spectro eye. The colourimetry practical session helped students try their hands on the setting up of colourimeter angle, measuring spot and special colours and understanding the specifications of measuring fluorescent and metallic colours. The charts and algorithms given to the students helped them compare the results of their measurement. |
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Date: 25-Aug-2008