Abstract <p>Previously, the gas temperature on the axis of the discharge with liquid non-metallic electrodes has been measured using the shadow background method. The discharge has been studied in the liquid cathode and metal anode configuration. Due to the features of the optical scheme, it has been impossible to obtain good spatial resolution, since the object under study is not in the focus of the photorecording device. As a result, the radial temperature variation is distorted by the instrument function of the lens. To restore the original distribution, it is necessary to solve the inverse problem. In this work, a method for restoring the radial temperature variation is proposed. First, two methods for solving the inverse convolution problem are compared on the basis of a model experiment. The method giving the best result is selected on the basis of the comparison results. The selected method is used to process the experimental data in order to restore the radial temperature variation.</p>