What is the Color Rendering?
The Color Rendering Index describes a light source’s ability to accurately reproduce different wavelengths of light. The higher the CRI, the more natural colors of objects and interior surfaces appear. Color rendering can be expressed using either the Ra or CRI index. These two measurements differ in scope, which is why the Ra value can sometimes appear numerically higher than the CRI value.
The CRI scale ranges from 0 to 100, where 100 represents perfect color rendering. LedStore’s product range includes luminaires with CRI values between 90 and 98, ensuring excellent color reproduction.
What is the Ra index?
The Ra index measures only part of the light spectrum, specifically eight values (R1–R8). For this reason, the Ra index does not provide as comprehensive information about a light source’s color rendering as broader metrics do. For example, the Ra index does not measure the R9 value, which represents red tones—typically the most challenging color for LED luminaires to reproduce accurately.
What is the CRI index?
The CRI index (Color Rendering Index) measures fifteen different color samples, covering values R1–R15. Compared to the Ra index, CRI provides a more accurate assessment of a light source’s color rendering, as it also includes the R9–R15 values.
Difference between the CRI and Ra indices
Ra index = R1–R8 (weighted toward blue–violet tones)
CRI index = R1–R15 (all colors, including red)
Read more on our blog:
https://ledstore.pro/blog/2020/04/28/colour-rendering-of-leds-what-is-the-difference-between-cri-and-ra
In the diagram below, the Ra value is 80, but the CRI is only around 70.
Typical CRI requirements
- Office lighting: The CRI should be at least 85, with a recommended level of CRI 90. High-quality light helps reduce eye strain and supports concentration.
- Video production: A very high CRI is required—ideally CRI 100, but at least CRI 95—to ensure accurate color reproduction on camera.
- Photography: A CRI of 95–100 is required so that colors appear natural and vibrant.
- Residential lighting: The recommended minimum is CRI 85, while the ideal level is CRI 90+. Good lighting ensures interior colors are rendered accurately.
- Industrial lighting: The minimum level is often CRI 70, but in manufacturing environments CRI 90 may be required. The typical color temperature is 4000 K.
CRI of LedStore luminaires
We strive to keep the photometric measurement data up to date for all LedStore luminaires. You can find the measurement results at the bottom of each product page under the “Attachments” tab. The same tab also includes the luminaires’ IES files.The color rendering index of LedStore LED luminaires is on average exceptionally high:
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LED panels and plafonds: CRI 93–98
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LED bulbs: CRI 95–98
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LED spotlights: CRI 95–98
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LED strips: CRI 95–98
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LED track lights: CRI 90
Below is an example showing the effect of color rendering when lighting fruit.
