measured with a sky scanner at the International Daylight Measurement Program station in
Lyon. Besides presentation of the sky luminance distribution, we also derive the CIE sky type
based on the CIE S 011/2003 standard. The CIE sky type is based on gradation and
indicatrix functions. Determination of the gradation and indicatrix group is based on the
calculation of luminance ratio between two elements on every almucantar. Since there are …