White Balance
Light is electromagnetic radiation that is made up of different wavelengths. CRI (measured as a score up to 100) refers to the Colour Rendering Index of a light source. This measures the ability of a light source to accurately reproduce the colours of the object it illuminates, or how evenly a light source emits different wavelengths. The more wavelengths a light source radiates, the better it can accurately render colour.
So how do we deal with these varying light sources when using a camera?
White balance refers to the camera setting that effects the colour temperature of your image. Different sources of light have different colour temperatures, measured in degrees Kelvin. Our eyes can adjust to the colour temperature of each light source to maintain a consistency of how colours appear. Cameras, though, need to be told what colour temperature the light is to achieve this.
Most cameras have varying ways of selecting white balance including in your cameras settings or a dedicated White Balance button on the camera body:
