IN MEMORIAM | Remembering Ian Ashdown, Senior Scientist, SunTracker Technologies

June 20, 2023
Lighting scientist, software engineer, and LEDs Magazine contributing author Ian Ashdown passed away recently.

Introduction by Carrie Meadows – With announcements from SunTracker Technologies

LEDs Magazine has learned that contributor and lighting engineering expert Ian Ashdown, PEng (Ret), passed away on June 14, 2023.

This news has shocked and saddened me personally as I have had the pleasure of communicating with Ian over the past few years on articles covering horticultural lighting as well as ultraviolet and visible light disinfection topics. Those who knew Ian or read his work will understand that he was meticulous in describing any optical radiation-related phenomenon, photometric, or application. I recently joked with Ian that if I understood half of what he wrote, it was probably just right for the engineering-minded readers in the LEDs audience.

A mathematician and software engineer, Ian put his skills and interests to use with great benefit to the lighting community, collaborating on Illuminating Engineering Society committees and participating as technical manuscript reviewer, advisor, and member of multiple societies and associations. As I write this, I am listening to a 2021 “Get a Grip on Lighting” podcast in which co-host Greg Ehrich asked Ian, “Which committee haven’t you been on for the IES?” See for yourself below in the full bio provided by Ian’s colleagues at SunTracker Technologies, along with the embedded LinkedIn tribute posted by the firm to Ian’s LinkedIn page.

Ian was a consummate scientist who continued to question and “look behind the curtain,” as he once put it, regarding the latest lighting research findings. I thoroughly enjoyed following his insights and debates on various test and measurement developments, software tools, lighting standards, and more. No question was too trivial; if he didn’t have an adequate response at the ready, he tracked down the research to support an informed response.

On behalf of LEDs Magazine, I send my deepest sympathies to Ian’s wife, Jan, and extended family, friends, and colleagues. We have collected links to all of the works authored by or featuring Ian Ashdown, published by LEDs Magazine, at the bottom of this page. Rest in peace, Ian, and thank you for sharing your deep knowledge of lighting. — Carrie Meadows


Ian Ashdown, P. Eng., FIES, was a renowned distinguished individual who made significant contributions in the field of lighting design, research and development, and software engineering. Until his death on June 14, 2023, Ian was the Senior Scientist and President of SunTracker Technologies — “Integrity in Lighting” in Victoria, BC. Ian had dedicated his life to developing cutting-edge lighting design software for various applications, including architecture, horticulture, entertainment, and health.

Ian has amassed a wealth of expertise and accomplishments throughout his remarkable career spanning over four decades.

  • Master’s degree in Computer Science (University of British Columbia, 2001)
  • Bachelor’s degree in Electrical Engineering (University of British Columbia, 1973)
  • Senior Scientist for SunTracker Technologies Ltd. (2011–present)
  • Chief Scientist for Lighting Analysts Inc. (1998–present)
  • Senior Scientist for Cooledge Lighting (2009–2014)
  • Senior Research Scientist for Philips Lighting (2007–2010)
  • Senior Research Scientist for TIR Systems Limited (2000–2007)
  • Head of Research for Ledalite Architectural Products (1990–2002)
  • Senior Software Engineer for Glenayre Research & Development (1986–1990)
  • Senior Electrical Engineer for Vancouver Skytrain Project (1981–1986)
  • Recipient of the 2017 Illuminating Engineering Society Medal
  • Fellow of the Illuminating Engineering Society (2001)
  • IES Sky Glow Committee Vice Chair (2017-present)
  • IES Computer Committee Chair (2009–2010)
  • SPIE Solid State Lighting Conference co-chair (2005–2009)
  • Illuminating Engineering Society (IES) Fellow (2001)
  • IES Calculations Committee Chair (1998–2000)
  • Editor of Chapter Nine of the IESNA Lighting Handbook, Ninth Edition (2000)
  • International Lighting Commission (CIE) Advisory Member
  • Optical Society of America Senior Member
  • Council for Optical Radiation Measurement (CORM) member
  • Journal of the Optical Society of America Technical Reviewer
  • Leukos Technical Reviewer
  • Morgan Kauffman / Elsevier Manuscript Reviewer
  • Author of Radiosity: A Programmer's Perspective (John Wiley & Sons, 1994)
  • Horticultural Lighting Committee Chair for ANSI/IES RP-45-21, Recommended Practice: Horticultural Lighting
  • 42+ academic papers, 98+ technical articles, more than 136 patents and patents pending, 6+ book chapters, et cetera.

Ian’s exceptional contributions have been recognized and honoured by his peers. He was awarded the Illuminating Engineering Society Medal in 2017 and became a Fellow of the Illuminating Engineering Society in 2001. Ian has also served in various leadership positions, including Vice Chair of the IES Sky Glow Committee (2017–present), Chair of the IES Computer Committee (2009–2010), and co-chair of the SPIE Solid State Lighting Conference (2005–2009). Moreover, he has made significant contributions as an author, reviewer, and advisory member for prominent organizations and publications.

With an enduring passion for mathematics and an unwavering fascination with light, Ian delved into diverse areas of exploration. His wide-ranging interests encompass photometric theory, eigenanalysis, genetic algorithms, and holographic techniques. Up to his death, he was actively engaged in several projects, such as intelligent lighting controls, real-time dynamic lighting design software, horticultural electric lighting, and daylighting.

When not immersed in his professional endeavours, Ian found solace in bike riding and hiking at elevations above 8,000 feet in the Canadian Rockies.

Ian looked at this ‘work’ as a hobby, something he loved to do, it was fun for him. (Listen to the “It’s just a hobby” podcast.)

For more information about Ian Ashdown and his work, you can visit the following links:

LEDs Magazine works featuring or authored by Ian Ashdown

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About the Author

Carrie Meadows | Editor-in-Chief, LEDs Magazine

Carrie Meadows has more than 20 years of experience in the publishing and media industry. She worked with the PennWell Technology Group for more than 17 years, having been part of the editorial staff at Solid State Technology, Microlithography World, Lightwave, Portable Design, CleanRooms, Laser Focus World, and Vision Systems Design before the group was acquired by current parent company Endeavor Business Media.

Meadows has received finalist recognition for LEDs Magazine in the FOLIO Eddie Awards, and has volunteered as a judge on several B2B editorial awards committees. She received a BA in English literature from Saint Anselm College, and earned thesis honors in the college's Geisel Library. Without the patience to sit down and write a book of her own, she has gladly undertaken the role of editor for the writings of friends and family.

Meadows enjoys living in the beautiful but sometimes unpredictable four seasons of the New England region, volunteering with an animal shelter, reading (of course), and walking with friends and extended "dog family" in her spare time.