Figure 12
From: Correlated color temperature is not a suitable proxy for the biological potency of light
Circadian Stimulus (CS) as a function of melanopic equivalent daylight illuminance (mel-EDI) with sub-divisions for photopic illuminance represented as boundaries of the data. (Top) Linear scaling for the x-axis. (Bottom) Logarithmic scaling for the x-axis. Overall, there is a wide range of achievable CS values at a fixed mel-EDI and a strong discontinuity due to the b-y spectral opponency of the CS model (“yellow wins” indicated by rBY-, and “blue wins” indicated by rBY+). No simple or satisfactory mathematical conversion between CS and mel-EDI can be offered. The grey shaded area indicates the sub-division of the data with an illuminance of 500 lx, which is enlarged in Fig. 13.
