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Two 20-channel absolute x-ray ultraviolet photodiode (AXUVD) cameras are being used on the large helical device for measuring the two-dimensional radiation distribution. The local radiation emissivity is obtained by inverting the measured brightnesses with linear (Tikhonov-Phillips) or nonlinear (maximum entropy) regularization methods. The most important features of these improved methods are the capability of reconstructing radiation distributions without any symmetry assumptions, built-in smoothing, and useful reconstructions with relatively few detector channels. Together with improvements in the analysis method, the current AXUVD system makes it possible to obtain radiation emissivity images of various localized radiative phenomena, such as radiation collapse or transport of impurities injected into the plasma.