A method for correcting focus drift of an imaging system. The method includes an imaging system obtaining a plurality of images of an object of interest with each image obtained at a different focus of the imaging system. A processor then determines image property values of each image of the plurality of images and determines an image quality metric from each image of the plurality of images. The processor then compares the image quality metric to a reference metric and determines, based on the comparison, if a focus drift has occurred, and further adjusts a focus of the imaging system if a focus drift has occurred.