Ok Im really confused with the whole kelvin temperature scale, and how it relates to photographic lighting. If anyone could explain this to me or give me a good website or book to read about it I would appreciate it.
Stated simply, the Kelvin scale gives the color of light radiated by a "black body" device at various temperatures on the Kelvin scale, where 0 is truly 0 - no molecular movement at all.
It turns out that the higher the temperature, the more blue and less red the light coming from the "black body" is. (No, I don't know exactly what that is).
So cooler temperatures tend towards the red end of the specturm, and higher temperatures tend towards the blue. This is counter-intuative to most people who think of reds as "hot" colors and blues as "cool" colors. But there you have it, the Universe doesn't take our personal preferences too seriously!
5500 degrees Kelvin is considered normal daylight, and most flashes are geared to output 5500 Kelvin. So daylight film is balanced to be used in daylight or flash. Thus, if you use early morning light or late evening light to photograph on daylight film (or a sensor set to 5500K), you get that "golden" sort of light. Personally, I like the effect, so even my digitals spend most of their time set to 5500K.
The color of the light emanated from a light source can be determined with a color-temperature light meter. These meters measure light in Kelvin color temperature units. Below is a list of color temperatures for different light sources.
Red or pink (2000 Kelvin before sunrise)
Red or pink (2800 to 3000 Kelvin at sunrise)
Red or pink (3200 to 3400 Kelvin 1 hour after sunrise)
Red or pink (3900 to 4100 Kelvin 2 hours after sunrise)
White (5000 to 5500 Kelvin around noon on bright sunny day)
Blue (6000 to 8000 Kelvin due to overcast sky)
Blue (7000 to 9000 Kelvin due to light shade)
Blue (10,000 to 11,000 Kelvin at a high altitude on a bright sunny day)
Blue (8,000 to 12,000 Kelvin due to heavy shade or rainy day)
Blue (11,000 to 18,000 Kelvin at a high altitude on an overcast day)
Red or pink (3900 to 4100 Kelvin 2 hours before sunset)
Red or pink (3200 to 3400 Kelvin 1 hour before sunset)