The thermal images received during the experiments KOSI 9, KOSI 10, KOSI 10A and KOSI 11 by a scanning infrared camera sensitive in the wavelength region 3-5 μm are discussed. The common features and the differences of the thermal behaviour of the samples during the different experiments are analysed. The results are compared with the data delivered by a nonimaging radiometer working in the wavelength region 8-14 μm. The main points of the discussion are the phenomena caused by the inhomogeneous character of the thermal surface processes. The observed distributions of the temperature on the surfaces of the samples were not static and are, therefore, not correlated with peculiarities of the sample preparation. This fact illustrates the complicated character of the thermal processes on the surface of an insolated ice-dust mixture.