082 - Types of Light Bulbs, Color Temperature, and CRI

Every type of light bulb produces different color quality, and two numbers on the spec sheet control everything: color temperature (CCT) measured in Kelvin, and the color rendering index (CRI) measured on a 0 to 100 scale. This episode covers both numbers and every major lamp type from incandescent to LED.

Layla walks through the Kelvin scale from warm 2700K residential lighting to cool 5000K daylight, then explains why CRI determines whether colors look natural or washed out under any light source. You will learn why a clothing store can look like a hospital waiting room when the CRI is wrong, even with plenty of light.

The episode covers all five lamp types: incandescent and halogen, fluorescent and CFL, HID (metal halide and high-pressure sodium), and LED. Each one is compared on color temperature, CRI, luminous efficacy in lumens per watt, lifespan, and practical tradeoffs like warm-up time, mercury content, and the difference between a ballast and a driver.

📝 Key topics covered:

Color temperature and the Kelvin scale (2700K to 5000K)

Color rendering index (CRI) benchmarks (80, 90, 95)

CCT vs CRI and why they are independent

Incandescent and halogen lighting

Fluorescent and CFL lighting

HID lighting: metal halide and high-pressure sodium

LED lighting, drivers, and L70 lifespan

Luminous efficacy and lumens vs watts