The colors contained in the visible light of the sun can be made visible through a prism - a triangle made of glass.
This creates a band of light with a continuous color progression from dark red to red-orange, yellow, green, blue, dark blue to dark violet.
This is called the spectrum of visible light.
The sun is the measure of light
The quality of light from the sun, with the colors it contains, is crucial to how humans perceive color.
You can't get more than the sun provides - sunlight is best suited to naturally depict or "render" all color shades and nuances.
This is why the so-called color rendering index (CRI) has been defined.
And this is for sunlight: CRI 100
Commercially available halogen lamps and LEDs are usually between 75 - 85 CRI.
Interesting to know:
The CRI value is defined for so-called test colors. There are a total of 14 such colors defined internationally, which are designated R1, R2... to R14.
Typically, LEDs are weakest especially at R9 (red) and miss a high CRI value here especially far.
A so-called full spectrum LED like the Soraa Vivid, on the other hand, achieves a CRI of well over 90 for all test colors.
In addition to the ability to reproduce all color nuances correctly and without gaps, the so-called color temperature also plays an important role.
Incandescent lamps can continuously serve the color spectrum, but are usually yellow to red in color.
Their color temperature is too low and is usually around 2000-4000 Kelvin.
Fluorescent lamps, on the other hand, can produce so-called white daylight with a color temperature of 5000-6000 Kelvin, but are incapable of producing a continuous color spectrum.
If you look at their light through a prism, you will find considerable gaps in the spectrum, colors are missing completely or are strongly underrepresented.
Everyone knows this: Monochromatic yellow light from street lighting at night swallows up almost all the colors of the otherwise colorful scenery in daylight.
Both - the color rendering index (CRI) and the color temperature are crucial for our perception of colors, contrasts and gradations of white.