Abstract: Various techniques are provided to perform flat field correction for infrared cameras. In one example, a method of calibrating an infrared camera includes calibrating a focal plane array (FPA) of the infrared camera to an external scene to determine a set of flat field correction values associated with a first optical path from the external scene to the FPA. The method also includes estimating a temperature difference between the FPA and a component of the infrared camera that is in proximity to the first optical path. The method also includes determining supplemental flat field correction values based on, at least in part, the first set of flat field correction values, where the supplemental flat field correction values are adjusted based on the estimated temperature difference before being applied to thermal image data obtained with the infrared camera. The method also includes storing the supplemental flat field correction values.