Correlated color temperature (CCT) and color rendering
index (CRI)

Is this e-book for you?

Are you responsible for determining the right ambiance and light quality for your application? Whether it comes to determining color temperature or color rendering index, there's one for every application.

In this e-book we help you determine what CCT and CRI are best for your office building, hotel, parking garage, retail stores, restaurant, etc.

Chapters include:

• Definitions
• A guide for choosing correlated color temperature (CCT)
• How to choose color rendering index (CRI): A practical guide
• Solving for color consistency

What is Correlated Color temperature (CCT)?

Color temperature (Correlated Color Temperature, or CCT) is essentially a gauge of how yellow or blue the color of light emitted from a light bulb appears. It’s measured in the Kelvin unit and is most commonly found between 2400 Kelvin degrees and 6500 Kelvin degrees. 

Warm light sources, such as incandescent bulbs, have a low color temperature (2400-3000K) and feature more light in the red/ orange/ yellow range.

Cool light sources, such as some HID or fluorescent lamps, have a high color temperature (>4000K) and feature more light in the blue range.

Our e-book gives temperature recommendations for specific applications to help you make the right decision for your building, garage, or parking lot. 

What is Color Rendering Index (CRI)?

CRI is a number between 0 and 100 that is used to determine how well a lighting product renders colors. The closer to 100, the better — or more true — colors should are supposed to look under a given product's light.

CRI is calculated based on how well a light source renders eight specific pastel colors. The theory is that if a light renders these colors well, it should render all colors well. 

In recent years, new alternative color measuring metrics have emerged, but CRI is still used as the main measurement for lighting color.