Electro-thermal feedback is utilized for removing thermal conductance between a bolometer's absorber element of a pixel in a thermal radiation sensor assembly and the environments through its mechanical support structure and electrical interconnects, thereby limiting the thermal conductance primarily through photon radiation. Zeroing the thermal conductance associated with the mechanical support structure and electrical interconnects is achieved by electro-thermal feedback that adjust the temperature of an intermediate stage of the mechanical support structure and electrical interconnects to equal the bolometer's absorber element temperature.