ANN LAIDLAW, ACL COLOR CONSULTING LLC ROLAND CONNELLY, ROLYN GROUP

Ann Laidlaw, ACL Color Consulting LLC
        Roland Connelly, RoLyn Group

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AATCC
   RA-36 Color Measurement Test Methods Committee
 AATCC will be producing illuminant weighting tables for use in instruments and software. These are
  calculated according to ASTM E2022 “Standard Practice for Calculation of Tristimulus Weighting
  Factors”. The SPDs will be supplied by a lighting company and the resultant tables will be distributed
  to any instrument/software provider who requests it. The goal is to make sure that with the rapid
  adoption of multiple new light sources, all parties making color-related calculations are working from
  the same illuminant data.

 RA-36 is working on a new color difference test method to replace TM173. The proposal will
  recommend CIEDE2000 as the primary metric going forward. DEcmc will still be included.

 RA-36 continues work on determining the appropriate levels of illumination for critical color
  judgements. This is a long term (several year) project.

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ISO
                                   TC38 SC1 / WG7
 Remote/electronic activity in 2017, not meeting in New Orleans this October.
 Will be looking at adopting CIEDE2000, update to ISO 105-J03
 No current visual evaluation method in ISO TC38. Will be looking at adopting a version of AATCC’s EP9
 – Visual Assessment of Color Difference of Textiles

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ASTM E-12
 An updated version of E308 – “Standard Practice for Computing the Color of Objects using the CIE
 System” has been completed. This moves all the table 6 illuminants to an appendix. These are the
 ones that have a band pass correction built into the tables. The recommendation is to use the
 preferred table 5 data, and use 5nm spectral data (either real or interpolated via cubic spline
 methods).

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CIE
 A new edition of Publication 15 is to be released in the next several months. Among many other
  changes, it will include a list of approximately 9 or 10 “typical” LED spectra. The printed version of all
  the illuminants will be at 5 nm interval, but 1 or 2 nm data will be available electronically (as is the
  case with all spectra)..
    The published spectra will be averages of example data (aligned with previously published
     illuminant data).
    Specific procedures required for measurement of data to be published by CIE.
 NOTE: AATCC will produce the illuminant weighting tables for these as soon as they are released.
 TC1.95 The Validity of the CIE Whiteness and Tint Equations (see next few slides)

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TC1.95
  The Validity of the CIE Whiteness and Tint Equations
Year Established: 2016

Terms of Reference: Based on published and new experimental work the TC shall seek to recommend
modifications to the existing CIE Whiteness and Tint Equations to extend their application to illuminants
other than D65. Furthermore the TC shall review the restrictions imposed on the validity of the equations
to samples that are measured on the same instrument at nearly the same time, and review the
colorimetric limits hitherto set. If enough experimental data justify it, the TC may recommend
modifications to the current CIE Equations for Whiteness and Tint.

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TC1.95
       The Validity of the CIE Whiteness and Tint Equations
 Chair: R Hirschler (HU)
 Members:

 Brill, Michael H. (US)        Popson, Todd (US)
 Carter, Ellen (US)            Sekulovski, Dragan (NL)
 Connelly, Roland (US)         Springsteen, Art (US)
 Grancaric, Ana Marija (HR)    Vik, Michal (CZ)
 Katayama, Ichiro (JP)         Wang, Binyu (CN)
 Luo, Ronnier (CN)             Wei, Minchen (CN)
 Nagy, Balázs Vince (BR/HU)    Yamanoi, Yuta (JP)
 Oliveira, Danielle (BR)       Zwart, Marc (JP)

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TC1.95 – Current Work in Process

 Develop multi-channel LED lighting cabinets for experiments.

 One experiment so far:
   In the experiment an LCD is used to present stimuli
   Paired comparison method is adopted for the evaluation.
   Two illumination conditions (D65 and D50) are simulated.
   Twelve experimental phases ( 4 CCTs x 3 UV levels) produced by a Thouslite LEDView cabinet
    with 14 types of LEDs including 3 UV LEDs.
   In total, 19,200 estimations were made, i.e. 8 observers x 12 phases x 50 samples x 4
    estimations (whiteness, whiteness%, white preference, hue).

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TC1.95 – Current Work in Process
 Committee members are testing and developing new whiteness indices:
    standard D65/10 CIE-W
    varying source CIE-W’
    CAT02

 The latter two gave similar performance and outperformed the present CIE-W.

 Find the limit
    -5>T>5, which is larger than the current -4

TC1.95 – Current Work in Progress

 Another experiment so far:

   Evaluation of two sets of white samples
       SET 1: 21 samples with neutral tint (former GEIGY calibration samples – cotton)
       SET 2: 30 samples made by Huntsman company containing different FWAs

   Visual assessment made by 10 color-normal observers – 3 replications

   Statistical evaluation indicates high correlation for inter-observer assessment:
          SET 1 = 0.997
          SET 2 = 0.876

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Summary
 CIE, ASTM, AATCC, ISO and other bodies are aligned in supporting updated colorimetry standards
 related to new illuminants
   Needed to support industrial color approval processes for LED sources
   Needed to establish timely method for updates for future lighting technologies

 SPDs for any source are not the same as physical source.
   Averaging, fixtures, surround, adaptation, etc, etc.
   Industrial color approval processes do not need to mimic POS environment.

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