The presence of in-gap states in solar cell absorbers that act as recombination centers can be detrimental for the photo-generated carriers’ lifetime and for the solar cell performance. In particular, the energetic position of these states (deep or shallow) is a very important parameter to identify since deep in-gap states yield higher recombination rate than shallow levels. This position is also related to the temperature dependence of the photo-transport properties, and therefore such measurements can help us answer the question of whether the photoconductivity is controlled by a deep or a shallow recombination level. A combination of Scanning Tunneling Spectroscopy (STS), by which the electronic level structure can be mapped, and temperature dependent photoconductivity (PC) properties, provide complementary information about these states and their influence on the photo-transport properties of the films and thus on the performance of the corresponding photovoltaic device. In this presentation, we demonstrate the advantageous of such combined study in two systems: MA_0.15FA_0.76Cs_0.06Pb(I_0.83Br_0.16)₃ (mixed cation perovskite (MCP)) and CuInSe₂. For the MCP system, we found a correlation between the energy distribution of the in-gap states and their manifestation in the photo-transport parameters of the film. In particular, our results suggest that the in-gap recombination centers for MCP are shallow (~0.2-0.3eV below the conduction band edge), which can be one of the reasons for the improved photovoltaic efficiency observed in this system relative to MAPbI₃. For the CuInSe₂ system, we found a correlation between the lack of Na passivation and a signature of a deep recombination level in the system and between the presence of planar defects and indications for shallow recombination level. The results suggest that it is favorable, from the carrier’s recombination point of view, to grow the thin film absorbers with a Cu-rich stage during the deposition process followed by a post deposition treatment of NaF.