What is Color Rendering Index (CRI) in Lighting?

When it comes to LED lighting, not all lights are created equal. One key factor that can significantly change how colors appear is CRI. Whether you're lighting up a workspace or retail environment or simply want your home to look its best, understanding the importance of CRI can help you choose lighting that brings out true-to-life colors and enhances the quality of any space. In this post, we'll explore why CRI matters and what it means for your LED lighting needs.

What is CRI in Lighting and Why is it Important?

CRI, or Color Rendering Index, measures a light source’s ability to show the true colors of objects compared to natural light. A higher CRI value indicates better color accuracy. For example, LED lights with a CRI of 80 or higher are generally good for most applications, while 90 and above is ideal for settings where color distinction is crucial, like retail spaces, art studios, and healthcare facilities.Beyond aesthetics, CRI impacts functionality and comfort. In office environments, high CRI lighting can reduce eye strain and improve accuracy for tasks that require color precision, such as graphic design or quality control in manufacturing. For homes, it enhances the visual appeal of interiors, making colors appear richer and more consistent, which can make all the difference in spaces where design and ambiance are key. Simply put, choosing LED lights with the right CRI makes your space more vibrant and functional.

What CRI Can’t Do

While CRI is a powerful tool for evaluating how well a light source renders colors, it has limits. It doesn’t measure brightness, color temperature, or how the light affects mood in a space. It also doesn’t account for specific tones of color rendition—meaning even two lights with the same CRI can produce slightly different visual effects. CRI is only one piece of the lighting puzzle, so it must be paired with considerations like lumen output and color temperature to meet your needs.

CCT vs. CRI

CCT, or Correlated Color Temperature, and CRI serve different functions in lighting but work together to create the desired effect. CCT measures the color appearance of light—whether it leans warm (yellow tones) or cool (blue tones). Think of CCT as setting the “mood” of the space: a 2700K light creates a warm, cozy atmosphere, while 5000K offers a bright, daylight-like feel. A high CRI paired with a well-chosen CCT in a retail store, for example, ensures products look appealing and true to their actual colors.

How CRI is Measured

CRI is measured on a scale from 0 to 100 by comparing a light source’s ability to render color against a reference light, typically natural daylight or incandescent light, which score close to 100. The measurement process involves assessing how well the light reproduces a set of standard color samples. A higher CRI score means that colors under that light appear more accurate and vibrant. To calculate CRI, a light source is tested across a range of colors to see how true they appear. If an LED has a CRI of 90 or above, it has excellent color accuracy, meaning objects will look almost the same as they do in natural light. LEDs with a CRI between 80 and 89 are considered good for most general applications. This standard scale makes it easy to evaluate lighting options based on how well they bring out true colors in your space.

The Relationship Between CRI and LED Lights

Unlike traditional light sources like incandescent bulbs, which naturally have high CRI, LEDs vary in color rendering ability. Some LEDs may have lower CRI scores, causing colors to appear dull or slightly off. However, with advancements in LED technology, many LEDs now offer high CRI options, often in the 90+ range, making them ideal for applications where color accuracy is key.

The relationship between CRI and LEDs is essential for applications like retail displays, photography, and healthcare, where true-to-life color rendering impacts both functionality and visual appeal. Choosing LEDs with a high CRI ensures the light quality matches the clarity and richness needed in these settings, providing energy efficiency without sacrificing color fidelity.

How to Choose the Right CRI Lighting

Choosing the right CRI for your lighting project depends on the type of space and the importance of accurate color representation. For most general-purpose applications like homes, offices, and warehouses, a CRI of 80+ is usually sufficient. This level provides good color accuracy for everyday use, creating a pleasant and functional environment without the added cost of extremely high CRI lighting.

However, if your space requires precise color accuracy—like retail stores, medical facilities, art galleries, or design studios—opting for LEDs with a CRI of 90+ is worth the investment. High CRI lighting brings out the rich, true colors in objects and surroundings, enhancing both aesthetics and usability. Think about how important color accuracy is in the space, then select a CRI that matches those needs to achieve the best lighting quality for your setting.

The Transition to TM-30-15

While CRI is important, there has been a recent shift to the TM-30-15 set of standards. TM-30-15, developed by the Illuminating Engineering Society (IES), is a more comprehensive and accurate method for evaluating a light source's color rendering capabilities. Unlike CRI, which measures color fidelity based on eight standard colors, TM-30-15 analyzes a broader set of 99 color samples, covering a wide range of hues found in real-world environments. This gives a much fuller picture of how a light source will render colors.

The shift to TM-30-15 is happening because CRI, though widely used, has limitations in capturing the nuances of color quality that modern lighting demands. TM-30-15 not only includes a measure of color fidelity (Rf) but also a measure of color gamut (Rg), which indicates whether colors appear more saturated or muted under a specific light. This dual approach provides more meaningful data, particularly for applications where color precision is crucial. As LED technology advances, TM-30-15 offers a more reliable standard for achieving lighting that meets the high expectations of today's users.

Choose e-conolight for Your CRI LED Needs!

When it comes to CRI LED lighting, e-conolight has you covered. Our selection of high-quality LED fixtures is designed to meet the diverse needs of any space, from retail and hospitality to healthcare and residential environments. With a range of CRI options, you can find the perfect lighting solution to bring out true-to-life colors and enhance the visual appeal of your space. Contact us today for help designing your LED lighting project (big or small)!