Why CRI R9 Matters

A high general CRI doesn’t guarantee a high R9 value, which is necessary to accurately see human skin tones.

Color rendering index (CRI) is a measurement of how much a light source shows the “true” colors of the objects it illuminates on a scale of 0 to 100. A higher CRI rating yields a better color rendering that is closer to natural sunlight and preferred by users.

CRI can be further broken down into sub-scores known as “R” values, which also have a maximum of 100. Each R value represents the light source’s color rendering ability for a particular color or shade. CRI is simply an average of the first 8 R values. Other R values, including R9, are critical color samples that are not included in the general CRI calculation. Many manufacturers will only report general CRI, so a light can have a high CRI, but a low R9 value.

 Image www.waveformlighting.com

R9 is the score that represents how accurately a light source will reproduce red colors. Red is a crucial color for many applications including photography, textiles and reflecting accurate human skin tones. Therefore, a light that lacks red will make a person look pale, or even green.

Image www.waveformlighting.com

R9 is a useful supplement to judge a light source’s color rendering ability. Séura’s Radiant LED Technology with 90+ CRI has an R9 value of 96 on a scale of 100, with 100 being the best. With Séura Radiant LED Technology, you’ll get the full color spectrum, including strong red colors.

Want to learn more about CRI and R9?

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