What is Color Rendering Index (CRI)?
Color Rendering Index-CRI is a quantitative unit used to measure the capacity of a light source to reflect the true colors of any object in place, compared to the natural light source.
We all know every light source is not the same. An object may reflect slightly different shades of color under different artificial lights like LED lighting, incandescent bulbs, and fluorescent and halogen light sources.
In simple terms, the closer the light source is to natural daylight, the more accurate the color rendering you see on the object. A red dress under a fluorescent light may not seem as radiant as it will in natural sunlight. Knowing this would make you aware of the luminaire you buy and its ability to showcase your place.
The following illustration will help you understand how the color rendering capability of an artificial light source affects what we see as a result. The color appearance of an object under consideration significantly deteriorates under a low CRI LED bulb.
Scientists have developed a way to quantify this phenomenon by using “Color Rendering Index-CRI” or “CIE Ra,” which is short for the international standard of color rendering index. Higher the CRI, the better the observed color scheme.
It should NOT be confused with the term “Correlated Color Temperature,” which is just a fancy way of describing the hue of light. However, the color temperatures do somewhat affect the CRI of a luminaire.
Where Do You See it?
You may find the value of CRI on the lamp package ranging from 0 to 100. Generally, the higher the number, the better, but it depends on the usage. A mid-range value may seem perfect for a living area but may not be as effective in an art gallery.
The value comes from a color rendering Index Chart. Here you can see it is pretty much self-explanatory.
How is it Measured?
CRI lighting is measured by comparing a light source’s color quality scale (color rendering score) to the ideal source, a perfect black body radiator, while keeping the color temperature fixed to 5000k. Various techniques, such as test methods, chromatic adaptation, and the R96a method, are used.
Why is Color Rendering Index Important?
Color Rendering Index-CRI is the most crucial thing to remember while setting up your LED light bulbs. It can significantly impact the appearance of furniture, the color of walls, décor, and overall ambiance.
As discussed before, not every light source is the same, and lamps with better CRI ratings can make a lot of difference.
Home lighting with a poor CRI rating can negatively impact your ability to see, read and set the right tone for the environment. Especially true for color-critical applications like drawing rooms, home studies, art expose, and research institutes. Always have a look at the luminaire package to buy the best product.
The CRI becomes even more critical for a commercial setup like in the textile and décor industry, where the manufactured product should have the same color appearance in the market.
LED technology evolves every day and now has better CRI ratings than ever. LEDs with a score of about 80 to 90 on color rendering charts are best suited for facade and landscape lighting.
How to Choose Color Rendering Index for Your LED Lighting
Color rendering index can easily make or break your lighting project. You want your interior to look vivid and reflect accurate colors, but at the same time, you may have a tight budget. How would you tackle this?
There may also be a case where your project doesn’t require high CRI, yet you put up high-quality CRI lighting products, wasting money and energy.
Let’s go through the critical steps that will help you decide the best CRI range:
Step 1) Define Your Application
The color rendering index solely depends on your application requirements. Let us help you define your application by putting forth some important questions.
Are colors important for your brand?
Some businesses are defined by their colors, mainly because marketers use specific colors for advertising the brand. Using the same colors in your project sets a mood that attracts customers.
In such cases, you need high color fidelity and light quality to bring out the accurate reflection of your project’s wall paint, furniture, and other decoration.
Restaurants, enterprises, and agencies that are represented with specific color combinations require CRI that accurately represents the brand.
Would the customer/visitors’ behavior be affected by the colors?
Retailing and merchandising are all about considering factors that will increase sales. It would be best if you had a high color rendering index for your buyers to select the best colors for outfits, makeup, apparel, home décor, etc.
Customers will most likely stay in your store for longer and eventually make a purchase. The light quality and display strategy highly influence your sales.
It can be any retail project, e.g., fruits, food items, jewelry, grocery stores, and shop windows. Go for a higher CRI of 90, wherever color rendition is important and you need improved aesthetics.
The lighting quality in malls should never disappoint potential customers.
Other than retail stores, projects that involve the ‘display’ of products or items, such as art galleries, museums, and car showcases, need perfect color quality.
Is the safety of people in your project important?
Projects where the safety of employees is a big concern, must be of high importance as human safety comes first.
Workers and technicians deal with dangerous equipment and machinery in factories and industries. Processes like cutting, welding, moving heavy equipment, melting materials, and production need properly lit areas.
In such instances, workers are usually exposed to danger during work hours. Any slight mishap due to poor visibility means severe consequences and fatal accidents.
You need higher wattages, but CRI plays a significant role in better visibility. You can achieve accurate visibility with even lower wattage bulbs.
Always prioritize using high-quality lights and CRIs > 90 for such applications.
Do your workers/employees need high visibility?
Hospitality projects such as offices, enterprise buildings, schools, universities, and industries need a kind of lighting that lets people see effortlessly. The lighting should increase productivity and reduce the chances of any eye disorder.
Warehouse and inventories where products are placed, packed and shipped require workers to identify the products and categorize SKUs quickly. Bad lighting and poor visibility will only set the schedule behind, resulting in bad performance and slow deliveries.
If your application entails working precision and long hours of stay, then choose a high CRI lighting of 80-90.
Other instances include spray booths, printing facilities, or art workshops, where colors should be clear and accurate for the painters and artists.
CRI especially comes into play in indoor applications. Performing strenuous tasks like studying, reading, or cooking food in the kitchen requires high-quality lighting and high CRIs.
Comparing the abovementioned applications with car parking, garages, and street lighting: You can do well with a CRI of 70-80 in outdoor areas. People need just enough illumination to help them navigate easily and feel secure, but you do not need high color fidelity in such places. Here we consider light output, lumens, and wattage more than CRI.
Step 2) What’s Your Budget?
High CRI lamps are slightly costly and have high phosphor levels, decreasing bulb efficiency. You will be wasting money if you choose high CRIs where it’s unnecessary.
The optimum solution is to go for mid-range CRI (80-90) in case you are tight on budget but need a good color fidelity.
If you’re looking for a long-term investment that’d pay you off for years and have a high budget, then go for CRI > 90. But don’t forget to define the requirements of your project.
Step 3) Test out!
Test the bulbs with different CRIs in your project. It is the smart way to figure out which LED bulb will accurately reproduce the colors in your project. Sometimes a mid-range CRI bulb gives better results than a high-level CRI bulb.
It comes down to your project area, the number of lights, and the wattages used type of applications to decide what works best. Keep this in mind. Sometimes theory can fail in practical application. So, test out your bulbs before making the big purchase.
Generally accepted CRIs for various applications:
|Project type||Examples||CRI Range|
|Indoor/Residential||Kitchen, study room, bedrooms, lounges||80-90|
|Hospitality||Restaurants, cafes, motels, hotels||80-95|
|Retails/Merchandising||Malls, fashion stores of all kinds, car showcases, art displays||90+|
|Business||Offices, schools, studios, hospitals, photography||90-97|
|Industries||Chemical/metal industries, production factories||90+|
|Others||Parking, garages, warehouses, and backyards||70-80|
Buy High CRI LED Lights from RC Lighting
RC Lighting is one of the leading LED lighting manufacturers that has helped many designers, artists, and contractors build their lighting projects from scratch. We have precise knowledge about the color rendering index and its combination with wattage, lumens, and brightness for optimum results.
Choose the highest CRI on the market today (95+), and let us help you specify the best wattage and CRI combination for your gig.