(a)
(b)
Figure 5: Illuminance measurements as a function of light meter readings. The dotted line in (a) shows the fitting straight line with a slope of 0.292. Bland-Altman plot in (b) shows the same measurement results but rescaled after using the slope value. Black line in (b) represents the mean value and grey lines the 5th and 95th percentiles of the difference distributions.