Figure 4

Spatial–temporal analysis of spectral weighting changes. (a) Spectral weighting obtained from Voigt fitting for all pixels, plotted against the corresponding illumination time. (b) Spectral weighting obtained from the steady state model after optimisation step to obtain \({k}_{CX}(x,y,t)\). (c) \({k}_{CX}\) plotted as a function of illumination time, for all spatial locations. (d) The rate of change of \({k}_{CX}\)(t) plotted against its instantaneous value at all time steps and all spatial locations. Linear fit shows that \({k}_{CX}(t)\) can be described by exponential decay, fitting the exponential form of \({k}_{CX}\) from Eq. (4) leads to the extraction of two parameters \({k}_{CX}^{0}\) and \(\beta \) for each pixel, visualised as maps in (e) and (f) respectively with logarithmic color scales for \({k}_{CX}^{0}\).