Why R9 matter for LED lights?

What is R9 and CRI?

For us to define the term R9, it is first important to understand what the Color Rendering Index is. Color Rendering Index is a rating system that measures the precision of how well a light source generates the color of an illuminated object. It gauges the light source’s capacity to display object colors “sensibly” or “normally” compared to a conversant reference source, either daylight or incandescent light. Color Rendering Index is an average value based on R1 to R8. R9 is one of the six saturated test colors not utilized in calculating CRI.
Since some percentage of the color Red can be found mixed into the various tints of most processed colors, the ability to precisely reproduce Red is key for accurately rendering colors of displayed objects. Lamps with high R9 values create the most vivid colors.
The Color Rendering Index metric is divided into 14 color ranges from R1 to R14. Color Rendition Index is an average value based on color ranges R1 to R8 of the metric, however, doesn’t consider the remaining six extra color references. A high CRI, matched with a high R9 value yields the most precise display of color.

Why is the R9 value important?

Reds are common in goods, skin tones and meats (if in a food store) and will the scene lively. They will make you look healthier in front of a mirror. They will make your store warm and welcoming. A luminaire with a high CRI but low R9 value will make your environment appear to be dull and boring. Many retailers have been caught out by what appears as an excellent luminaire with a CRI of 80 and more, however for reasons unknown; the final scheme simply doesn’t appear to be as exciting as hoped. This is basically because a low R9 value is striking once again.


Regardless of whether in the hospital, a craftsmanship exhibition, eatery, or private home, the color red is essential all together for the human eye to understand pure colors. A high R9 value shows a more precise illustration of the actual color.

So what CRI and R9 value would it be advisable for me to look for?

Traditionally, LED items have been muted as giving a decent light quality when they have a Color Rendering Index of at least 80 and an R9 estimation of more than 0. In some applications, this is valid. Clearly, most industrial environments and some commercial environments you don’t require a high R9 value despite the fact that you couldn’t go wrong if you did. However, for the cases of retail, print, therapeutic or art to give some examples, a high R9 value is of paramount significance and you ought to search for a CRI of no less than 90 and an R9 estimation of no less than 60. This is a standard for most of Myledy led strip lights.

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