Topics of Interest

It’s All About You

Ian Ashdown, P. Eng., FIES

Chief Scientist, Lighting Analysts Inc.

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What interests you? This is a question that all journalists must face at some point: if I write an article on some esoteric topic, will anyone care? Will you care?

Thankfully, in this age of Big Data, I can at least do a post-mortem analysis of your interests. What really interests you as lighting designers is … well, it’s interesting.

The data collection aspect of this analysis was easy: I simply counted your visits (and nothing more) to the individual All Things Lighting blog articles, then plotted the results:

Topics of Interest - FIG. 1

FIG. 1 – All Things Lighting article page visits.

Understanding your interests is more challenging. For example, what is your ongoing fascination with Daylight Factors? It is a complete mystery to me, as daylight factors were arguably the worst idea that has ever been proposed for daylight design when they were introduced 150 years ago. Their usefulness as a daylight design tool is even less today.

Your interest in Photometry and Photosynthesis is equally fascinating. This is basically about lighting design for horticultural applications. The article itself came from an enquiry about lighting design for … umm, medicinal plants … in Colorado, but the popularity of the topic is still surprising. (On the other hand, a projected market of ten billion dollars a year might explain some of the interest – that’s a lot of horticultural lighting business.)

Nighttime light pollution? This topic comprises Color Temperature and Outdoor Lighting, Light Pollution and Uplight Ratings, and the decidedly offbeat Mobile Light Pollution and Botanical Light Pollution articles. What is perhaps the most surprising about this is that the Light Pollution and Uplight Ratings article is arguably more germane to outdoor lighting design than Color Temperature and Outdoor Lighting, and yet look at the difference in popularity. Very strange, but it is heartening to see that you are taking an interest in this social responsibility topic.

Your interest in mesopic photometry, including both Understanding Mesopic Photometry and Mesopic Photometry and Statistics, is equally puzzling. Mesopic roadway lighting was a hot topic five years ago, but without official recognition as a design criterion by the IES Roadway Lighting Committee and other roadway lighting standards organizations, it seems like a somewhat esoteric topic today.

Now, The Kruithof Curve and Kruithof Revisited … if only there were some way to delete this topic from the collective consciousness of the lighting design community! If daylight factors are useless, the Kruithof Curve is in a category of its own. Still, it continues to attract your attention.

What is equally surprising is the apparent lack of interest in human centric lighting (Entraining Circadian Rhythms and Seeing Ultraviolet), intelligent lighting, visible light communications, and IoT (Giving Light), and the purported dangers of high-CCT light (Blue Light Hazard … or Not?). Not even Web search terms have managed to rescue these articles from relative obscurity.

The remaining articles are, as they say, background noise. They were very interesting to research and write about, but clearly not leading Web search terms.

Not to worry, however – even knowing your interests provides me with ideas for future blog articles. If daylight factors have attracted the most interest, it will fascinating to see your response to the forthcoming Climate-Based Daylight Modeling article.