MinisterofDOOM wrote:
Actually, temperature is EXACTLY what "K" means. 4000K means 4000 degrees Kelvin. Different temperatures produce different bandwidths of light, which is what determines a lamp's color.
Technically, you're both in the same ballpark. In context of light bulbs (HID capsules specifically) the Kelvin rating describes light "temperature" or "hue". In this case "temperature" is not in the same sense as "today's high is 74 degrees with low of 60". It is a indicator of color in the visible spectrum of light. Brightness, on the other hand, is measured by Lumens.