dc589da6_iew_of_Canon_s_pro_digital_SLR__Description
[Setting] Overcast [Colour Temp. (Kelvin)] 6000K [Description] 
Neutralizes colour casts on cloudy days. The EOS-1D manual suggests this setting for sunsets and sunrises, presumably to emphasize the warmth in the scene.
Rob Galbraith DPI: Canon EOS-1D: a preview of Canon's pro digital SLR
Description