Art Adams is skeptical of the TLCI Color Rendering Index

Funny, I've always been sceptical of Art Adams, and whilst he does have a point about DSC Labs being better and more accurate than MacBeth, I'd take his conclusions about TLCI with a grain of salt - he was, as noted in the article, affiliated with that company for a number of years.
 
To-date, on my constant hunt for new and interesting lighting kit that creates new options for rigging and lighting scenes, the TLCI index seems to have proved highly accurate as to the colour quality of various sources. They say that anything above 90, should be totally fine with no need for any kind of corrections, and (so far, at least) all of the lights I've tested (on the strength of their high TLCI ratings) have proved extremely solid.

So as far as I can tell, it's the most reliable standard of measurement we have for colour quality at the moment.
 
Interesting articles there, thanks for the links.
The main message I took away from the "TLCI and Color Rendering Index" article was that the methodology of the TLCI research was (according to Adams) somewhat opaque concerning the cameras that were used to obtain the initial test data. That surprised me, as I would have presumed this information would have readily available. After all, people post all sorts of comparative camera tests all the time, and we all know (by using our eyeballs, seeing these tests and from our own first-hand experiences) that different models and makes of camera can have very differing looks that can be hard to match sometimes - as declared in the "TLCI and Camera Color" article.
(Yes, I know most of these kinds of informal tests are not scientific at all, but we know there are differences.)


But page 11 of the document that Adams quoted - https://tech.ebu.ch/docs/tech/tech3353.pdf - states:
"From all the data collected to date it has become clear that there are only relatively small differences between types and manufacturers"
Take from this what you will.

TLCI is good, but the question of how well it caters for modern single-chip cameras vs. 3-chip cameras should, in my view, still be held to some scrutiny, because it does seem quite apparent that single-chip systems behave slightly differently in their colour response to 3-chip systems. It's very fair to assume that most of us here use single-chip cameras now, so it's not a small concern.
Although how much it matters, in regard to most people's everyday use of brand xx LED with brand xx camera, is debatable and subject to much personal interpretation and taste when scopes are not involved. When it's all said and done, trusting our eyes with the final product is still a good method.
 
There is no way of objectively characterising a light source as a single number, or even several numbers, such that no lack or excess of energy at a given frequency could not cause a problem with photography by coinciding with the reflective spectrum of some surface. TLCI is certainly imperfect. CRI is imperfect. So would any such measure be.

As to Art's piece, my feeling is that the problem lies with single-chip cameras and the apparently unquenchable thirst for more resolution and more dynamic range, which drive manufacturers to use reduced-saturation filters.
 
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