A method of performing non-uniformity correction for an imaging system includes receiving image data from a detector. The method also includes retrieving stored correction coefficients from the memory. The method also includes retrieving a stored factory calibration reference frame. The method also includes acquiring an operational calibration reference frame. The method also includes computing updated correction coefficients based on the stored correction coefficients, the stored factory calibration reference frame, and the operational calibration reference frame. The method also includes computing the non-uniformity correction based on the updated correction coefficients. The method also includes forming a corrected image by applying the non-uniformity correction to the image data. The method further includes outputting the corrected image.