1. A method for generating a display of an image of a patient's internal anatomy in a surgical field during a medical procedure, comprising: acquiring a high resolution baseline image of the surgical field including the patient's internal anatomy in a baseline orientation; digitally manipulating the high resolution baseline image to produce a baseline image set including representative images of the baseline image at a plurality of permutations of movements of the baseline image from the baseline orientation; acquiring a new image of the surgical field at a lower resolution; comparing the new image to the representative images in the baseline image set and selecting the representative image having an acceptable degree of correlation with the new image; and merging the selected representative image with the new image and displaying the merged image.