New colour metrics proposed for characterising lighting
23 September 2015
News
Opto-Electronics
Accurately quantifying the colour rendition characteristics of a light source is a complex problem.
Many aspects of colour rendition, such as colour fidelity, colour discrimination or colour preference, should be simultaneously considered during the design and specification process. At present there is no one metric or measure that can accurately quantify all aspects of colour rendition and/or identify the most desirable light source for every application.
The Illuminating Engineering Society (IES) has now published a technical memorandum – TM-30-15 – which describes a method for evaluating light source colour rendition that takes an objective and statistical approach, quantifying the fidelity (closeness to a reference) and gamut (increase or decrease in chroma) of a light source. The colour metric applies to the characterisation of both LED-based solid-state lighting (SSL) and legacy sources, and has been proposed to the International Commission on Illumination (CIE) for adoption as an industry standard.
Although based on the new colour samples, the new Rf fidelity metric is similar to CRI, while the new Rg gamut metric is based on the Gamut Area Index (GAI). The new method also generates a colour vector graphic that indicates average hue and chroma shifts, and which helps with interpreting the values of Rf and Rg.
TM-30-15 provides equations and direction for calculating Rf and Rg, including the spectral reflectance functions for the 99 CES (colour evaluation samples). It is accompanied by a software tool to aid in calculation and display of the results; access information for the software tool is provided in the publication.
The IES TM-30-15 colour rendition method consolidates and synthesises numerous research efforts that have been ongoing for several years, and was developed by representatives of the manufacturing, specification and research segments of the lighting industry. The technical memorandum is available for purchase from the IES website.
For more information visit www.ies.org
Further reading:
From the Editor's desk: Growth through inclusivity
Technews Publishing
News
As the engineering fields in South Africa continue to make progress toward gender equality, we are finally starting to see the presence and contribution of women in engineering and industrial roles.
Read more...
KITE 2025 proves its value
News
The KwaZulu-Natal Industrial Technology Exhibition (KITE) 2025 confirmed its place as KwaZulu-Natal’s must-attend industrial event, drawing thousands of industry professionals.
Read more...
Otto Wireless Solutions announces promotion of Miyelani Kubayi to technical director
Otto Wireless Solutions
News
Otto Wireless Solutions is proud to announce the promotion of Miyelani Kubayi to the position of technical director, effective 1 August 2025.
Read more...
DMASS experiences continued slowdown
News
The European electronic components distribution market continued its downward trajectory in the second quarter of 2025, according to new figures released by DMASS.
Read more...
World-first zero second grid-to-backup power switch
News
JSE-listed cable manufacturer, South Ocean Electric Wire, has completed a solar installation it says marks a global first: a seamless switch from grid to backup power in zero seconds.
Read more...
News
OMC deploys cobots to improve throughput 10x, while maintaining quality and ensuring consistency of fibre optic production.
Read more...
Cobots for opto production line
News
OMC deploys cobots to improve throughput 10x, while maintaining quality and ensuring consistency of fibre optic production.
Read more...
SACEEC celebrates standout industrial innovation on the KITE 2025 show floor
News
Exhibitor innovation took the spotlight at the KITE 2025 as the South African Capital Equipment Export Council announced the winners of its prestigious New Product & Innovation Awards.
Read more...
SA team for International Olympiad in Informatics
News
The Institute of Information Technology Professionals South Africa has named the team that will represent South Africa at this year’s International Olympiad in Informatics.
Read more...
Anritsu and Bluetest to support OTA measurement
News
Anritsu Company and Sweden-based Bluetest AB have jointly developed an Over-The-Air measurement solution to evaluate the performance of 5G IoT devices compliant with the RedCap specification.
Read more...
printer friendly version