Quote Originally Posted by Stephen Benskin
The definitive research was done by Loyd Jones and his team at Kodak in the 1930s and 1940s. the seminal paper on the subject of illuminance of daylight is Sunlight and Skylight as Determinants of Photographic Exposure. I. Luminous Density as Determined by Solar Altitude and Atmospheric Conditions. and II. Scene Structure, Directional Index, Photographic efficiency of Daylight, Safety Factors, and Evaluation of Camera Exposure, JOSA, vol 38 and 39, Feb 1948 and Feb 1948.
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Stephen, I have to ask this... How long did it take you to dig up this reference?


(BTW - this was not making fun or taking a cheap shot)