Embodiments described herein may operate to image a scene with an imaging system using an image blurring technique. An image sensor array (ISA) element may be identified as a dark defect element if a first ratio of an average of a set of illuminance signal magnitudes from a set of surrounding ISA elements to a magnitude of an illuminance signal from the ISA element is greater than a threshold sharpness value. The image sensor array element may be identified as a bright defect element if a second ratio of the magnitude of the illuminance signal from the ISA element to the average of the set of illuminance signal magnitudes from the set of surrounding ISA elements is greater than the threshold sharpness value.